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Diffstat (limited to 'docs/sqlglot/transforms.html')
| -rw-r--r-- | docs/sqlglot/transforms.html | 602 |
1 files changed, 349 insertions, 253 deletions
diff --git a/docs/sqlglot/transforms.html b/docs/sqlglot/transforms.html index 04b2bbf..e29c207 100644 --- a/docs/sqlglot/transforms.html +++ b/docs/sqlglot/transforms.html @@ -37,6 +37,9 @@ <a class="function" href="#eliminate_distinct_on">eliminate_distinct_on</a> </li> <li> + <a class="function" href="#eliminate_qualify">eliminate_qualify</a> + </li> + <li> <a class="function" href="#remove_precision_parameterized_types">remove_precision_parameterized_types</a> </li> <li> @@ -72,146 +75,180 @@ </span><span id="L-2"><a href="#L-2"><span class="linenos"> 2</span></a> </span><span id="L-3"><a href="#L-3"><span class="linenos"> 3</span></a><span class="kn">import</span> <span class="nn">typing</span> <span class="k">as</span> <span class="nn">t</span> </span><span id="L-4"><a href="#L-4"><span class="linenos"> 4</span></a> -</span><span id="L-5"><a href="#L-5"><span class="linenos"> 5</span></a><span class="kn">from</span> <span class="nn">sqlglot.helper</span> <span class="kn">import</span> <span class="n">find_new_name</span> -</span><span id="L-6"><a href="#L-6"><span class="linenos"> 6</span></a> -</span><span id="L-7"><a href="#L-7"><span class="linenos"> 7</span></a><span class="k">if</span> <span class="n">t</span><span class="o">.</span><span class="n">TYPE_CHECKING</span><span class="p">:</span> -</span><span id="L-8"><a href="#L-8"><span class="linenos"> 8</span></a> <span class="kn">from</span> <span class="nn">sqlglot.generator</span> <span class="kn">import</span> <span class="n">Generator</span> -</span><span id="L-9"><a href="#L-9"><span class="linenos"> 9</span></a> -</span><span id="L-10"><a href="#L-10"><span class="linenos"> 10</span></a><span class="kn">from</span> <span class="nn">sqlglot</span> <span class="kn">import</span> <span class="n">expressions</span> <span class="k">as</span> <span class="n">exp</span> +</span><span id="L-5"><a href="#L-5"><span class="linenos"> 5</span></a><span class="kn">from</span> <span class="nn">sqlglot</span> <span class="kn">import</span> <span class="n">expressions</span> <span class="k">as</span> <span class="n">exp</span> +</span><span id="L-6"><a href="#L-6"><span class="linenos"> 6</span></a><span class="kn">from</span> <span class="nn">sqlglot.helper</span> <span class="kn">import</span> <span class="n">find_new_name</span> +</span><span id="L-7"><a href="#L-7"><span class="linenos"> 7</span></a> +</span><span id="L-8"><a href="#L-8"><span class="linenos"> 8</span></a><span class="k">if</span> <span class="n">t</span><span class="o">.</span><span class="n">TYPE_CHECKING</span><span class="p">:</span> +</span><span id="L-9"><a href="#L-9"><span class="linenos"> 9</span></a> <span class="kn">from</span> <span class="nn">sqlglot.generator</span> <span class="kn">import</span> <span class="n">Generator</span> +</span><span id="L-10"><a href="#L-10"><span class="linenos"> 10</span></a> </span><span id="L-11"><a href="#L-11"><span class="linenos"> 11</span></a> -</span><span id="L-12"><a href="#L-12"><span class="linenos"> 12</span></a> -</span><span id="L-13"><a href="#L-13"><span class="linenos"> 13</span></a><span class="k">def</span> <span class="nf">unalias_group</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="L-14"><a href="#L-14"><span class="linenos"> 14</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="L-15"><a href="#L-15"><span class="linenos"> 15</span></a><span class="sd"> Replace references to select aliases in GROUP BY clauses.</span> -</span><span id="L-16"><a href="#L-16"><span class="linenos"> 16</span></a> -</span><span id="L-17"><a href="#L-17"><span class="linenos"> 17</span></a><span class="sd"> Example:</span> -</span><span id="L-18"><a href="#L-18"><span class="linenos"> 18</span></a><span class="sd"> >>> import sqlglot</span> -</span><span id="L-19"><a href="#L-19"><span class="linenos"> 19</span></a><span class="sd"> >>> sqlglot.parse_one("SELECT a AS b FROM x GROUP BY b").transform(unalias_group).sql()</span> -</span><span id="L-20"><a href="#L-20"><span class="linenos"> 20</span></a><span class="sd"> 'SELECT a AS b FROM x GROUP BY 1'</span> -</span><span id="L-21"><a href="#L-21"><span class="linenos"> 21</span></a> -</span><span id="L-22"><a href="#L-22"><span class="linenos"> 22</span></a><span class="sd"> Args:</span> -</span><span id="L-23"><a href="#L-23"><span class="linenos"> 23</span></a><span class="sd"> expression: the expression that will be transformed.</span> -</span><span id="L-24"><a href="#L-24"><span class="linenos"> 24</span></a> -</span><span id="L-25"><a href="#L-25"><span class="linenos"> 25</span></a><span class="sd"> Returns:</span> -</span><span id="L-26"><a href="#L-26"><span class="linenos"> 26</span></a><span class="sd"> The transformed expression.</span> -</span><span id="L-27"><a href="#L-27"><span class="linenos"> 27</span></a><span class="sd"> """</span> -</span><span id="L-28"><a href="#L-28"><span class="linenos"> 28</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">):</span> -</span><span id="L-29"><a href="#L-29"><span class="linenos"> 29</span></a> <span class="n">aliased_selects</span> <span class="o">=</span> <span class="p">{</span> -</span><span id="L-30"><a href="#L-30"><span class="linenos"> 30</span></a> <span class="n">e</span><span class="o">.</span><span class="n">alias</span><span class="p">:</span> <span class="n">i</span> -</span><span id="L-31"><a href="#L-31"><span class="linenos"> 31</span></a> <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">e</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="o">.</span><span class="n">expressions</span><span class="p">,</span> <span class="n">start</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span> -</span><span id="L-32"><a href="#L-32"><span class="linenos"> 32</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">e</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Alias</span><span class="p">)</span> -</span><span id="L-33"><a href="#L-33"><span class="linenos"> 33</span></a> <span class="p">}</span> -</span><span id="L-34"><a href="#L-34"><span class="linenos"> 34</span></a> -</span><span id="L-35"><a href="#L-35"><span class="linenos"> 35</span></a> <span class="k">for</span> <span class="n">group_by</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">expressions</span><span class="p">:</span> -</span><span id="L-36"><a href="#L-36"><span class="linenos"> 36</span></a> <span class="k">if</span> <span class="p">(</span> -</span><span id="L-37"><a href="#L-37"><span class="linenos"> 37</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">group_by</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)</span> -</span><span id="L-38"><a href="#L-38"><span class="linenos"> 38</span></a> <span class="ow">and</span> <span class="ow">not</span> <span class="n">group_by</span><span class="o">.</span><span class="n">table</span> -</span><span id="L-39"><a href="#L-39"><span class="linenos"> 39</span></a> <span class="ow">and</span> <span class="n">group_by</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">aliased_selects</span> -</span><span id="L-40"><a href="#L-40"><span class="linenos"> 40</span></a> <span class="p">):</span> -</span><span id="L-41"><a href="#L-41"><span class="linenos"> 41</span></a> <span class="n">group_by</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">Literal</span><span class="o">.</span><span class="n">number</span><span class="p">(</span><span class="n">aliased_selects</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">group_by</span><span class="o">.</span><span class="n">name</span><span class="p">)))</span> -</span><span id="L-42"><a href="#L-42"><span class="linenos"> 42</span></a> -</span><span id="L-43"><a href="#L-43"><span class="linenos"> 43</span></a> <span class="k">return</span> <span class="n">expression</span> +</span><span id="L-12"><a href="#L-12"><span class="linenos"> 12</span></a><span class="k">def</span> <span class="nf">unalias_group</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="L-13"><a href="#L-13"><span class="linenos"> 13</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-14"><a href="#L-14"><span class="linenos"> 14</span></a><span class="sd"> Replace references to select aliases in GROUP BY clauses.</span> +</span><span id="L-15"><a href="#L-15"><span class="linenos"> 15</span></a> +</span><span id="L-16"><a href="#L-16"><span class="linenos"> 16</span></a><span class="sd"> Example:</span> +</span><span id="L-17"><a href="#L-17"><span class="linenos"> 17</span></a><span class="sd"> >>> import sqlglot</span> +</span><span id="L-18"><a href="#L-18"><span class="linenos"> 18</span></a><span class="sd"> >>> sqlglot.parse_one("SELECT a AS b FROM x GROUP BY b").transform(unalias_group).sql()</span> +</span><span id="L-19"><a href="#L-19"><span class="linenos"> 19</span></a><span class="sd"> 'SELECT a AS b FROM x GROUP BY 1'</span> +</span><span id="L-20"><a href="#L-20"><span class="linenos"> 20</span></a> +</span><span id="L-21"><a href="#L-21"><span class="linenos"> 21</span></a><span class="sd"> Args:</span> +</span><span id="L-22"><a href="#L-22"><span class="linenos"> 22</span></a><span class="sd"> expression: the expression that will be transformed.</span> +</span><span id="L-23"><a href="#L-23"><span class="linenos"> 23</span></a> +</span><span id="L-24"><a href="#L-24"><span class="linenos"> 24</span></a><span class="sd"> Returns:</span> +</span><span id="L-25"><a href="#L-25"><span class="linenos"> 25</span></a><span class="sd"> The transformed expression.</span> +</span><span id="L-26"><a href="#L-26"><span class="linenos"> 26</span></a><span class="sd"> """</span> +</span><span id="L-27"><a href="#L-27"><span class="linenos"> 27</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">):</span> +</span><span id="L-28"><a href="#L-28"><span class="linenos"> 28</span></a> <span class="n">aliased_selects</span> <span class="o">=</span> <span class="p">{</span> +</span><span id="L-29"><a href="#L-29"><span class="linenos"> 29</span></a> <span class="n">e</span><span class="o">.</span><span class="n">alias</span><span class="p">:</span> <span class="n">i</span> +</span><span id="L-30"><a href="#L-30"><span class="linenos"> 30</span></a> <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">e</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="o">.</span><span class="n">expressions</span><span class="p">,</span> <span class="n">start</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span> +</span><span id="L-31"><a href="#L-31"><span class="linenos"> 31</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">e</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Alias</span><span class="p">)</span> +</span><span id="L-32"><a href="#L-32"><span class="linenos"> 32</span></a> <span class="p">}</span> +</span><span id="L-33"><a href="#L-33"><span class="linenos"> 33</span></a> +</span><span id="L-34"><a href="#L-34"><span class="linenos"> 34</span></a> <span class="k">for</span> <span class="n">group_by</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">expressions</span><span class="p">:</span> +</span><span id="L-35"><a href="#L-35"><span class="linenos"> 35</span></a> <span class="k">if</span> <span class="p">(</span> +</span><span id="L-36"><a href="#L-36"><span class="linenos"> 36</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">group_by</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)</span> +</span><span id="L-37"><a href="#L-37"><span class="linenos"> 37</span></a> <span class="ow">and</span> <span class="ow">not</span> <span class="n">group_by</span><span class="o">.</span><span class="n">table</span> +</span><span id="L-38"><a href="#L-38"><span class="linenos"> 38</span></a> <span class="ow">and</span> <span class="n">group_by</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">aliased_selects</span> +</span><span id="L-39"><a href="#L-39"><span class="linenos"> 39</span></a> <span class="p">):</span> +</span><span id="L-40"><a href="#L-40"><span class="linenos"> 40</span></a> <span class="n">group_by</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">Literal</span><span class="o">.</span><span class="n">number</span><span class="p">(</span><span class="n">aliased_selects</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">group_by</span><span class="o">.</span><span class="n">name</span><span class="p">)))</span> +</span><span id="L-41"><a href="#L-41"><span class="linenos"> 41</span></a> +</span><span id="L-42"><a href="#L-42"><span class="linenos"> 42</span></a> <span class="k">return</span> <span class="n">expression</span> +</span><span id="L-43"><a href="#L-43"><span class="linenos"> 43</span></a> </span><span id="L-44"><a href="#L-44"><span class="linenos"> 44</span></a> -</span><span id="L-45"><a href="#L-45"><span class="linenos"> 45</span></a> -</span><span id="L-46"><a href="#L-46"><span class="linenos"> 46</span></a><span class="k">def</span> <span class="nf">eliminate_distinct_on</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="L-47"><a href="#L-47"><span class="linenos"> 47</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="L-48"><a href="#L-48"><span class="linenos"> 48</span></a><span class="sd"> Convert SELECT DISTINCT ON statements to a subquery with a window function.</span> -</span><span id="L-49"><a href="#L-49"><span class="linenos"> 49</span></a> -</span><span id="L-50"><a href="#L-50"><span class="linenos"> 50</span></a><span class="sd"> This is useful for dialects that don't support SELECT DISTINCT ON but support window functions.</span> -</span><span id="L-51"><a href="#L-51"><span class="linenos"> 51</span></a> -</span><span id="L-52"><a href="#L-52"><span class="linenos"> 52</span></a><span class="sd"> Args:</span> -</span><span id="L-53"><a href="#L-53"><span class="linenos"> 53</span></a><span class="sd"> expression: the expression that will be transformed.</span> -</span><span id="L-54"><a href="#L-54"><span class="linenos"> 54</span></a> -</span><span id="L-55"><a href="#L-55"><span class="linenos"> 55</span></a><span class="sd"> Returns:</span> -</span><span id="L-56"><a href="#L-56"><span class="linenos"> 56</span></a><span class="sd"> The transformed expression.</span> -</span><span id="L-57"><a href="#L-57"><span class="linenos"> 57</span></a><span class="sd"> """</span> -</span><span id="L-58"><a href="#L-58"><span class="linenos"> 58</span></a> <span class="k">if</span> <span class="p">(</span> -</span><span id="L-59"><a href="#L-59"><span class="linenos"> 59</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> -</span><span id="L-60"><a href="#L-60"><span class="linenos"> 60</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"distinct"</span><span class="p">)</span> -</span><span id="L-61"><a href="#L-61"><span class="linenos"> 61</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"on"</span><span class="p">)</span> -</span><span id="L-62"><a href="#L-62"><span class="linenos"> 62</span></a> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Tuple</span><span class="p">)</span> -</span><span id="L-63"><a href="#L-63"><span class="linenos"> 63</span></a> <span class="p">):</span> -</span><span id="L-64"><a href="#L-64"><span class="linenos"> 64</span></a> <span class="n">distinct_cols</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">]</span><span class="o">.</span><span class="n">expressions</span> -</span><span id="L-65"><a href="#L-65"><span class="linenos"> 65</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span> -</span><span id="L-66"><a href="#L-66"><span class="linenos"> 66</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span> -</span><span id="L-67"><a href="#L-67"><span class="linenos"> 67</span></a> <span class="n">row_number</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_row_number"</span><span class="p">)</span> -</span><span id="L-68"><a href="#L-68"><span class="linenos"> 68</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">(</span> -</span><span id="L-69"><a href="#L-69"><span class="linenos"> 69</span></a> <span class="n">this</span><span class="o">=</span><span class="n">exp</span><span class="o">.</span><span class="n">RowNumber</span><span class="p">(),</span> -</span><span id="L-70"><a href="#L-70"><span class="linenos"> 70</span></a> <span class="n">partition_by</span><span class="o">=</span><span class="n">distinct_cols</span><span class="p">,</span> -</span><span id="L-71"><a href="#L-71"><span class="linenos"> 71</span></a> <span class="p">)</span> -</span><span id="L-72"><a href="#L-72"><span class="linenos"> 72</span></a> <span class="n">order</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"order"</span><span class="p">)</span> -</span><span id="L-73"><a href="#L-73"><span class="linenos"> 73</span></a> <span class="k">if</span> <span class="n">order</span><span class="p">:</span> -</span><span id="L-74"><a href="#L-74"><span class="linenos"> 74</span></a> <span class="n">window</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="s2">"order"</span><span class="p">,</span> <span class="n">order</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> -</span><span id="L-75"><a href="#L-75"><span class="linenos"> 75</span></a> <span class="n">order</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span> -</span><span id="L-76"><a href="#L-76"><span class="linenos"> 76</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">row_number</span><span class="p">)</span> -</span><span id="L-77"><a href="#L-77"><span class="linenos"> 77</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> -</span><span id="L-78"><a href="#L-78"><span class="linenos"> 78</span></a> <span class="k">return</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="n">outer_selects</span><span class="p">)</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">())</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="sa">f</span><span class="s1">'"</span><span class="si">{</span><span class="n">row_number</span><span class="si">}</span><span class="s1">" = 1'</span><span class="p">)</span> -</span><span id="L-79"><a href="#L-79"><span class="linenos"> 79</span></a> <span class="k">return</span> <span class="n">expression</span> -</span><span id="L-80"><a href="#L-80"><span class="linenos"> 80</span></a> -</span><span id="L-81"><a href="#L-81"><span class="linenos"> 81</span></a> -</span><span id="L-82"><a href="#L-82"><span class="linenos"> 82</span></a><span class="k">def</span> <span class="nf">remove_precision_parameterized_types</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="L-83"><a href="#L-83"><span class="linenos"> 83</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="L-84"><a href="#L-84"><span class="linenos"> 84</span></a><span class="sd"> Some dialects only allow the precision for parameterized types to be defined in the DDL and not in other expressions.</span> -</span><span id="L-85"><a href="#L-85"><span class="linenos"> 85</span></a><span class="sd"> This transforms removes the precision from parameterized types in expressions.</span> -</span><span id="L-86"><a href="#L-86"><span class="linenos"> 86</span></a><span class="sd"> """</span> -</span><span id="L-87"><a href="#L-87"><span class="linenos"> 87</span></a> <span class="k">return</span> <span class="n">expression</span><span class="o">.</span><span class="n">transform</span><span class="p">(</span> -</span><span id="L-88"><a href="#L-88"><span class="linenos"> 88</span></a> <span class="k">lambda</span> <span class="n">node</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">(</span> -</span><span id="L-89"><a href="#L-89"><span class="linenos"> 89</span></a> <span class="o">**</span><span class="p">{</span> -</span><span id="L-90"><a href="#L-90"><span class="linenos"> 90</span></a> <span class="o">**</span><span class="n">node</span><span class="o">.</span><span class="n">args</span><span class="p">,</span> -</span><span id="L-91"><a href="#L-91"><span class="linenos"> 91</span></a> <span class="s2">"expressions"</span><span class="p">:</span> <span class="p">[</span> -</span><span id="L-92"><a href="#L-92"><span class="linenos"> 92</span></a> <span class="n">node_expression</span> -</span><span id="L-93"><a href="#L-93"><span class="linenos"> 93</span></a> <span class="k">for</span> <span class="n">node_expression</span> <span class="ow">in</span> <span class="n">node</span><span class="o">.</span><span class="n">expressions</span> -</span><span id="L-94"><a href="#L-94"><span class="linenos"> 94</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node_expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> -</span><span id="L-95"><a href="#L-95"><span class="linenos"> 95</span></a> <span class="p">],</span> -</span><span id="L-96"><a href="#L-96"><span class="linenos"> 96</span></a> <span class="p">}</span> -</span><span id="L-97"><a href="#L-97"><span class="linenos"> 97</span></a> <span class="p">)</span> -</span><span id="L-98"><a href="#L-98"><span class="linenos"> 98</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> -</span><span id="L-99"><a href="#L-99"><span class="linenos"> 99</span></a> <span class="k">else</span> <span class="n">node</span><span class="p">,</span> -</span><span id="L-100"><a href="#L-100"><span class="linenos">100</span></a> <span class="p">)</span> +</span><span id="L-45"><a href="#L-45"><span class="linenos"> 45</span></a><span class="k">def</span> <span class="nf">eliminate_distinct_on</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="L-46"><a href="#L-46"><span class="linenos"> 46</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-47"><a href="#L-47"><span class="linenos"> 47</span></a><span class="sd"> Convert SELECT DISTINCT ON statements to a subquery with a window function.</span> +</span><span id="L-48"><a href="#L-48"><span class="linenos"> 48</span></a> +</span><span id="L-49"><a href="#L-49"><span class="linenos"> 49</span></a><span class="sd"> This is useful for dialects that don't support SELECT DISTINCT ON but support window functions.</span> +</span><span id="L-50"><a href="#L-50"><span class="linenos"> 50</span></a> +</span><span id="L-51"><a href="#L-51"><span class="linenos"> 51</span></a><span class="sd"> Args:</span> +</span><span id="L-52"><a href="#L-52"><span class="linenos"> 52</span></a><span class="sd"> expression: the expression that will be transformed.</span> +</span><span id="L-53"><a href="#L-53"><span class="linenos"> 53</span></a> +</span><span id="L-54"><a href="#L-54"><span class="linenos"> 54</span></a><span class="sd"> Returns:</span> +</span><span id="L-55"><a href="#L-55"><span class="linenos"> 55</span></a><span class="sd"> The transformed expression.</span> +</span><span id="L-56"><a href="#L-56"><span class="linenos"> 56</span></a><span class="sd"> """</span> +</span><span id="L-57"><a href="#L-57"><span class="linenos"> 57</span></a> <span class="k">if</span> <span class="p">(</span> +</span><span id="L-58"><a href="#L-58"><span class="linenos"> 58</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> +</span><span id="L-59"><a href="#L-59"><span class="linenos"> 59</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"distinct"</span><span class="p">)</span> +</span><span id="L-60"><a href="#L-60"><span class="linenos"> 60</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"on"</span><span class="p">)</span> +</span><span id="L-61"><a href="#L-61"><span class="linenos"> 61</span></a> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Tuple</span><span class="p">)</span> +</span><span id="L-62"><a href="#L-62"><span class="linenos"> 62</span></a> <span class="p">):</span> +</span><span id="L-63"><a href="#L-63"><span class="linenos"> 63</span></a> <span class="n">distinct_cols</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">]</span><span class="o">.</span><span class="n">expressions</span> +</span><span id="L-64"><a href="#L-64"><span class="linenos"> 64</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span> +</span><span id="L-65"><a href="#L-65"><span class="linenos"> 65</span></a> <span class="n">row_number</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_row_number"</span><span class="p">)</span> +</span><span id="L-66"><a href="#L-66"><span class="linenos"> 66</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">(</span> +</span><span id="L-67"><a href="#L-67"><span class="linenos"> 67</span></a> <span class="n">this</span><span class="o">=</span><span class="n">exp</span><span class="o">.</span><span class="n">RowNumber</span><span class="p">(),</span> +</span><span id="L-68"><a href="#L-68"><span class="linenos"> 68</span></a> <span class="n">partition_by</span><span class="o">=</span><span class="n">distinct_cols</span><span class="p">,</span> +</span><span id="L-69"><a href="#L-69"><span class="linenos"> 69</span></a> <span class="p">)</span> +</span><span id="L-70"><a href="#L-70"><span class="linenos"> 70</span></a> <span class="n">order</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"order"</span><span class="p">)</span> +</span><span id="L-71"><a href="#L-71"><span class="linenos"> 71</span></a> <span class="k">if</span> <span class="n">order</span><span class="p">:</span> +</span><span id="L-72"><a href="#L-72"><span class="linenos"> 72</span></a> <span class="n">window</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="s2">"order"</span><span class="p">,</span> <span class="n">order</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> +</span><span id="L-73"><a href="#L-73"><span class="linenos"> 73</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">row_number</span><span class="p">)</span> +</span><span id="L-74"><a href="#L-74"><span class="linenos"> 74</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="L-75"><a href="#L-75"><span class="linenos"> 75</span></a> <span class="k">return</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="n">outer_selects</span><span class="p">)</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">())</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="sa">f</span><span class="s1">'"</span><span class="si">{</span><span class="n">row_number</span><span class="si">}</span><span class="s1">" = 1'</span><span class="p">)</span> +</span><span id="L-76"><a href="#L-76"><span class="linenos"> 76</span></a> <span class="k">return</span> <span class="n">expression</span> +</span><span id="L-77"><a href="#L-77"><span class="linenos"> 77</span></a> +</span><span id="L-78"><a href="#L-78"><span class="linenos"> 78</span></a> +</span><span id="L-79"><a href="#L-79"><span class="linenos"> 79</span></a><span class="k">def</span> <span class="nf">eliminate_qualify</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="L-80"><a href="#L-80"><span class="linenos"> 80</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-81"><a href="#L-81"><span class="linenos"> 81</span></a><span class="sd"> Convert SELECT statements that contain the QUALIFY clause into subqueries, filtered equivalently.</span> +</span><span id="L-82"><a href="#L-82"><span class="linenos"> 82</span></a> +</span><span id="L-83"><a href="#L-83"><span class="linenos"> 83</span></a><span class="sd"> The idea behind this transformation can be seen in Snowflake's documentation for QUALIFY:</span> +</span><span id="L-84"><a href="#L-84"><span class="linenos"> 84</span></a><span class="sd"> https://docs.snowflake.com/en/sql-reference/constructs/qualify</span> +</span><span id="L-85"><a href="#L-85"><span class="linenos"> 85</span></a> +</span><span id="L-86"><a href="#L-86"><span class="linenos"> 86</span></a><span class="sd"> Some dialects don't support window functions in the WHERE clause, so we need to include them as</span> +</span><span id="L-87"><a href="#L-87"><span class="linenos"> 87</span></a><span class="sd"> projections in the subquery, in order to refer to them in the outer filter using aliases. Also,</span> +</span><span id="L-88"><a href="#L-88"><span class="linenos"> 88</span></a><span class="sd"> if a column is referenced in the QUALIFY clause but is not selected, we need to include it too,</span> +</span><span id="L-89"><a href="#L-89"><span class="linenos"> 89</span></a><span class="sd"> otherwise we won't be able to refer to it in the outer query's WHERE clause.</span> +</span><span id="L-90"><a href="#L-90"><span class="linenos"> 90</span></a><span class="sd"> """</span> +</span><span id="L-91"><a href="#L-91"><span class="linenos"> 91</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"qualify"</span><span class="p">):</span> +</span><span id="L-92"><a href="#L-92"><span class="linenos"> 92</span></a> <span class="n">taken</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">)</span> +</span><span id="L-93"><a href="#L-93"><span class="linenos"> 93</span></a> <span class="k">for</span> <span class="n">select</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span><span class="p">:</span> +</span><span id="L-94"><a href="#L-94"><span class="linenos"> 94</span></a> <span class="k">if</span> <span class="ow">not</span> <span class="n">select</span><span class="o">.</span><span class="n">alias_or_name</span><span class="p">:</span> +</span><span id="L-95"><a href="#L-95"><span class="linenos"> 95</span></a> <span class="n">alias</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">taken</span><span class="p">,</span> <span class="s2">"_c"</span><span class="p">)</span> +</span><span id="L-96"><a href="#L-96"><span class="linenos"> 96</span></a> <span class="n">select</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">select</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">alias</span><span class="p">))</span> +</span><span id="L-97"><a href="#L-97"><span class="linenos"> 97</span></a> <span class="n">taken</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">alias</span><span class="p">)</span> +</span><span id="L-98"><a href="#L-98"><span class="linenos"> 98</span></a> +</span><span id="L-99"><a href="#L-99"><span class="linenos"> 99</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="p">[</span><span class="n">select</span><span class="o">.</span><span class="n">alias_or_name</span> <span class="k">for</span> <span class="n">select</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span><span class="p">])</span> +</span><span id="L-100"><a href="#L-100"><span class="linenos">100</span></a> <span class="n">qualify_filters</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"qualify"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">this</span> </span><span id="L-101"><a href="#L-101"><span class="linenos">101</span></a> -</span><span id="L-102"><a href="#L-102"><span class="linenos">102</span></a> -</span><span id="L-103"><a href="#L-103"><span class="linenos">103</span></a><span class="k">def</span> <span class="nf">preprocess</span><span class="p">(</span> -</span><span id="L-104"><a href="#L-104"><span class="linenos">104</span></a> <span class="n">transforms</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">List</span><span class="p">[</span><span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">]],</span> -</span><span id="L-105"><a href="#L-105"><span class="linenos">105</span></a> <span class="n">to_sql</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">],</span> -</span><span id="L-106"><a href="#L-106"><span class="linenos">106</span></a><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">]:</span> -</span><span id="L-107"><a href="#L-107"><span class="linenos">107</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="L-108"><a href="#L-108"><span class="linenos">108</span></a><span class="sd"> Creates a new transform by chaining a sequence of transformations and converts the resulting</span> -</span><span id="L-109"><a href="#L-109"><span class="linenos">109</span></a><span class="sd"> expression to SQL, using an appropriate `Generator.TRANSFORMS` function.</span> -</span><span id="L-110"><a href="#L-110"><span class="linenos">110</span></a> -</span><span id="L-111"><a href="#L-111"><span class="linenos">111</span></a><span class="sd"> Args:</span> -</span><span id="L-112"><a href="#L-112"><span class="linenos">112</span></a><span class="sd"> transforms: sequence of transform functions. These will be called in order.</span> -</span><span id="L-113"><a href="#L-113"><span class="linenos">113</span></a><span class="sd"> to_sql: final transform that converts the resulting expression to a SQL string.</span> +</span><span id="L-102"><a href="#L-102"><span class="linenos">102</span></a> <span class="k">for</span> <span class="n">expr</span> <span class="ow">in</span> <span class="n">qualify_filters</span><span class="o">.</span><span class="n">find_all</span><span class="p">((</span><span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)):</span> +</span><span id="L-103"><a href="#L-103"><span class="linenos">103</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expr</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">):</span> +</span><span id="L-104"><a href="#L-104"><span class="linenos">104</span></a> <span class="n">alias</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_w"</span><span class="p">)</span> +</span><span id="L-105"><a href="#L-105"><span class="linenos">105</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">expr</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">alias</span><span class="p">),</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="L-106"><a href="#L-106"><span class="linenos">106</span></a> <span class="n">expr</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">column</span><span class="p">(</span><span class="n">alias</span><span class="p">))</span> +</span><span id="L-107"><a href="#L-107"><span class="linenos">107</span></a> <span class="k">elif</span> <span class="n">expr</span><span class="o">.</span><span class="n">name</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">:</span> +</span><span id="L-108"><a href="#L-108"><span class="linenos">108</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">expr</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="L-109"><a href="#L-109"><span class="linenos">109</span></a> +</span><span id="L-110"><a href="#L-110"><span class="linenos">110</span></a> <span class="k">return</span> <span class="n">outer_selects</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">(</span><span class="n">alias</span><span class="o">=</span><span class="s2">"_t"</span><span class="p">))</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">qualify_filters</span><span class="p">)</span> +</span><span id="L-111"><a href="#L-111"><span class="linenos">111</span></a> +</span><span id="L-112"><a href="#L-112"><span class="linenos">112</span></a> <span class="k">return</span> <span class="n">expression</span> +</span><span id="L-113"><a href="#L-113"><span class="linenos">113</span></a> </span><span id="L-114"><a href="#L-114"><span class="linenos">114</span></a> -</span><span id="L-115"><a href="#L-115"><span class="linenos">115</span></a><span class="sd"> Returns:</span> -</span><span id="L-116"><a href="#L-116"><span class="linenos">116</span></a><span class="sd"> Function that can be used as a generator transform.</span> -</span><span id="L-117"><a href="#L-117"><span class="linenos">117</span></a><span class="sd"> """</span> -</span><span id="L-118"><a href="#L-118"><span class="linenos">118</span></a> -</span><span id="L-119"><a href="#L-119"><span class="linenos">119</span></a> <span class="k">def</span> <span class="nf">_to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">):</span> -</span><span id="L-120"><a href="#L-120"><span class="linenos">120</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">0</span><span class="p">](</span><span class="n">expression</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> -</span><span id="L-121"><a href="#L-121"><span class="linenos">121</span></a> <span class="k">for</span> <span class="n">t</span> <span class="ow">in</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">1</span><span class="p">:]:</span> -</span><span id="L-122"><a href="#L-122"><span class="linenos">122</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">t</span><span class="p">(</span><span class="n">expression</span><span class="p">)</span> -</span><span id="L-123"><a href="#L-123"><span class="linenos">123</span></a> <span class="k">return</span> <span class="n">to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">)</span> -</span><span id="L-124"><a href="#L-124"><span class="linenos">124</span></a> -</span><span id="L-125"><a href="#L-125"><span class="linenos">125</span></a> <span class="k">return</span> <span class="n">_to_sql</span> -</span><span id="L-126"><a href="#L-126"><span class="linenos">126</span></a> -</span><span id="L-127"><a href="#L-127"><span class="linenos">127</span></a> -</span><span id="L-128"><a href="#L-128"><span class="linenos">128</span></a><span class="k">def</span> <span class="nf">delegate</span><span class="p">(</span><span class="n">attr</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">:</span> -</span><span id="L-129"><a href="#L-129"><span class="linenos">129</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="L-130"><a href="#L-130"><span class="linenos">130</span></a><span class="sd"> Create a new method that delegates to `attr`. This is useful for creating `Generator.TRANSFORMS`</span> -</span><span id="L-131"><a href="#L-131"><span class="linenos">131</span></a><span class="sd"> functions that delegate to existing generator methods.</span> -</span><span id="L-132"><a href="#L-132"><span class="linenos">132</span></a><span class="sd"> """</span> -</span><span id="L-133"><a href="#L-133"><span class="linenos">133</span></a> -</span><span id="L-134"><a href="#L-134"><span class="linenos">134</span></a> <span class="k">def</span> <span class="nf">_transform</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> -</span><span id="L-135"><a href="#L-135"><span class="linenos">135</span></a> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr</span><span class="p">)(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> -</span><span id="L-136"><a href="#L-136"><span class="linenos">136</span></a> -</span><span id="L-137"><a href="#L-137"><span class="linenos">137</span></a> <span class="k">return</span> <span class="n">_transform</span> -</span><span id="L-138"><a href="#L-138"><span class="linenos">138</span></a> -</span><span id="L-139"><a href="#L-139"><span class="linenos">139</span></a> -</span><span id="L-140"><a href="#L-140"><span class="linenos">140</span></a><span class="n">UNALIAS_GROUP</span> <span class="o">=</span> <span class="p">{</span><span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">unalias_group</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"group_sql"</span><span class="p">))}</span> -</span><span id="L-141"><a href="#L-141"><span class="linenos">141</span></a><span class="n">ELIMINATE_DISTINCT_ON</span> <span class="o">=</span> <span class="p">{</span><span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">eliminate_distinct_on</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"select_sql"</span><span class="p">))}</span> -</span><span id="L-142"><a href="#L-142"><span class="linenos">142</span></a><span class="n">REMOVE_PRECISION_PARAMETERIZED_TYPES</span> <span class="o">=</span> <span class="p">{</span> -</span><span id="L-143"><a href="#L-143"><span class="linenos">143</span></a> <span class="n">exp</span><span class="o">.</span><span class="n">Cast</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">remove_precision_parameterized_types</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"cast_sql"</span><span class="p">))</span> -</span><span id="L-144"><a href="#L-144"><span class="linenos">144</span></a><span class="p">}</span> +</span><span id="L-115"><a href="#L-115"><span class="linenos">115</span></a><span class="k">def</span> <span class="nf">remove_precision_parameterized_types</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="L-116"><a href="#L-116"><span class="linenos">116</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-117"><a href="#L-117"><span class="linenos">117</span></a><span class="sd"> Some dialects only allow the precision for parameterized types to be defined in the DDL and not in other expressions.</span> +</span><span id="L-118"><a href="#L-118"><span class="linenos">118</span></a><span class="sd"> This transforms removes the precision from parameterized types in expressions.</span> +</span><span id="L-119"><a href="#L-119"><span class="linenos">119</span></a><span class="sd"> """</span> +</span><span id="L-120"><a href="#L-120"><span class="linenos">120</span></a> <span class="k">return</span> <span class="n">expression</span><span class="o">.</span><span class="n">transform</span><span class="p">(</span> +</span><span id="L-121"><a href="#L-121"><span class="linenos">121</span></a> <span class="k">lambda</span> <span class="n">node</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">(</span> +</span><span id="L-122"><a href="#L-122"><span class="linenos">122</span></a> <span class="o">**</span><span class="p">{</span> +</span><span id="L-123"><a href="#L-123"><span class="linenos">123</span></a> <span class="o">**</span><span class="n">node</span><span class="o">.</span><span class="n">args</span><span class="p">,</span> +</span><span id="L-124"><a href="#L-124"><span class="linenos">124</span></a> <span class="s2">"expressions"</span><span class="p">:</span> <span class="p">[</span> +</span><span id="L-125"><a href="#L-125"><span class="linenos">125</span></a> <span class="n">node_expression</span> +</span><span id="L-126"><a href="#L-126"><span class="linenos">126</span></a> <span class="k">for</span> <span class="n">node_expression</span> <span class="ow">in</span> <span class="n">node</span><span class="o">.</span><span class="n">expressions</span> +</span><span id="L-127"><a href="#L-127"><span class="linenos">127</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node_expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> +</span><span id="L-128"><a href="#L-128"><span class="linenos">128</span></a> <span class="p">],</span> +</span><span id="L-129"><a href="#L-129"><span class="linenos">129</span></a> <span class="p">}</span> +</span><span id="L-130"><a href="#L-130"><span class="linenos">130</span></a> <span class="p">)</span> +</span><span id="L-131"><a href="#L-131"><span class="linenos">131</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> +</span><span id="L-132"><a href="#L-132"><span class="linenos">132</span></a> <span class="k">else</span> <span class="n">node</span><span class="p">,</span> +</span><span id="L-133"><a href="#L-133"><span class="linenos">133</span></a> <span class="p">)</span> +</span><span id="L-134"><a href="#L-134"><span class="linenos">134</span></a> +</span><span id="L-135"><a href="#L-135"><span class="linenos">135</span></a> +</span><span id="L-136"><a href="#L-136"><span class="linenos">136</span></a><span class="k">def</span> <span class="nf">preprocess</span><span class="p">(</span> +</span><span id="L-137"><a href="#L-137"><span class="linenos">137</span></a> <span class="n">transforms</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">List</span><span class="p">[</span><span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">]],</span> +</span><span id="L-138"><a href="#L-138"><span class="linenos">138</span></a> <span class="n">to_sql</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">],</span> +</span><span id="L-139"><a href="#L-139"><span class="linenos">139</span></a><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">]:</span> +</span><span id="L-140"><a href="#L-140"><span class="linenos">140</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-141"><a href="#L-141"><span class="linenos">141</span></a><span class="sd"> Creates a new transform by chaining a sequence of transformations and converts the resulting</span> +</span><span id="L-142"><a href="#L-142"><span class="linenos">142</span></a><span class="sd"> expression to SQL, using an appropriate `Generator.TRANSFORMS` function.</span> +</span><span id="L-143"><a href="#L-143"><span class="linenos">143</span></a> +</span><span id="L-144"><a href="#L-144"><span class="linenos">144</span></a><span class="sd"> Args:</span> +</span><span id="L-145"><a href="#L-145"><span class="linenos">145</span></a><span class="sd"> transforms: sequence of transform functions. These will be called in order.</span> +</span><span id="L-146"><a href="#L-146"><span class="linenos">146</span></a><span class="sd"> to_sql: final transform that converts the resulting expression to a SQL string.</span> +</span><span id="L-147"><a href="#L-147"><span class="linenos">147</span></a> +</span><span id="L-148"><a href="#L-148"><span class="linenos">148</span></a><span class="sd"> Returns:</span> +</span><span id="L-149"><a href="#L-149"><span class="linenos">149</span></a><span class="sd"> Function that can be used as a generator transform.</span> +</span><span id="L-150"><a href="#L-150"><span class="linenos">150</span></a><span class="sd"> """</span> +</span><span id="L-151"><a href="#L-151"><span class="linenos">151</span></a> +</span><span id="L-152"><a href="#L-152"><span class="linenos">152</span></a> <span class="k">def</span> <span class="nf">_to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">):</span> +</span><span id="L-153"><a href="#L-153"><span class="linenos">153</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">0</span><span class="p">](</span><span class="n">expression</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> +</span><span id="L-154"><a href="#L-154"><span class="linenos">154</span></a> <span class="k">for</span> <span class="n">t</span> <span class="ow">in</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">1</span><span class="p">:]:</span> +</span><span id="L-155"><a href="#L-155"><span class="linenos">155</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">t</span><span class="p">(</span><span class="n">expression</span><span class="p">)</span> +</span><span id="L-156"><a href="#L-156"><span class="linenos">156</span></a> <span class="k">return</span> <span class="n">to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">)</span> +</span><span id="L-157"><a href="#L-157"><span class="linenos">157</span></a> +</span><span id="L-158"><a href="#L-158"><span class="linenos">158</span></a> <span class="k">return</span> <span class="n">_to_sql</span> +</span><span id="L-159"><a href="#L-159"><span class="linenos">159</span></a> +</span><span id="L-160"><a href="#L-160"><span class="linenos">160</span></a> +</span><span id="L-161"><a href="#L-161"><span class="linenos">161</span></a><span class="k">def</span> <span class="nf">delegate</span><span class="p">(</span><span class="n">attr</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">:</span> +</span><span id="L-162"><a href="#L-162"><span class="linenos">162</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="L-163"><a href="#L-163"><span class="linenos">163</span></a><span class="sd"> Create a new method that delegates to `attr`. This is useful for creating `Generator.TRANSFORMS`</span> +</span><span id="L-164"><a href="#L-164"><span class="linenos">164</span></a><span class="sd"> functions that delegate to existing generator methods.</span> +</span><span id="L-165"><a href="#L-165"><span class="linenos">165</span></a><span class="sd"> """</span> +</span><span id="L-166"><a href="#L-166"><span class="linenos">166</span></a> +</span><span id="L-167"><a href="#L-167"><span class="linenos">167</span></a> <span class="k">def</span> <span class="nf">_transform</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> +</span><span id="L-168"><a href="#L-168"><span class="linenos">168</span></a> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr</span><span class="p">)(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> +</span><span id="L-169"><a href="#L-169"><span class="linenos">169</span></a> +</span><span id="L-170"><a href="#L-170"><span class="linenos">170</span></a> <span class="k">return</span> <span class="n">_transform</span> +</span><span id="L-171"><a href="#L-171"><span class="linenos">171</span></a> +</span><span id="L-172"><a href="#L-172"><span class="linenos">172</span></a> +</span><span id="L-173"><a href="#L-173"><span class="linenos">173</span></a><span class="n">UNALIAS_GROUP</span> <span class="o">=</span> <span class="p">{</span><span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">unalias_group</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"group_sql"</span><span class="p">))}</span> +</span><span id="L-174"><a href="#L-174"><span class="linenos">174</span></a><span class="n">ELIMINATE_DISTINCT_ON</span> <span class="o">=</span> <span class="p">{</span><span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">eliminate_distinct_on</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"select_sql"</span><span class="p">))}</span> +</span><span id="L-175"><a href="#L-175"><span class="linenos">175</span></a><span class="n">ELIMINATE_QUALIFY</span> <span class="o">=</span> <span class="p">{</span><span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">eliminate_qualify</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"select_sql"</span><span class="p">))}</span> +</span><span id="L-176"><a href="#L-176"><span class="linenos">176</span></a><span class="n">REMOVE_PRECISION_PARAMETERIZED_TYPES</span> <span class="o">=</span> <span class="p">{</span> +</span><span id="L-177"><a href="#L-177"><span class="linenos">177</span></a> <span class="n">exp</span><span class="o">.</span><span class="n">Cast</span><span class="p">:</span> <span class="n">preprocess</span><span class="p">([</span><span class="n">remove_precision_parameterized_types</span><span class="p">],</span> <span class="n">delegate</span><span class="p">(</span><span class="s2">"cast_sql"</span><span class="p">))</span> +</span><span id="L-178"><a href="#L-178"><span class="linenos">178</span></a><span class="p">}</span> </span></pre></div> @@ -227,37 +264,37 @@ </div> <a class="headerlink" href="#unalias_group"></a> - <div class="pdoc-code codehilite"><pre><span></span><span id="unalias_group-14"><a href="#unalias_group-14"><span class="linenos">14</span></a><span class="k">def</span> <span class="nf">unalias_group</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="unalias_group-15"><a href="#unalias_group-15"><span class="linenos">15</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="unalias_group-16"><a href="#unalias_group-16"><span class="linenos">16</span></a><span class="sd"> Replace references to select aliases in GROUP BY clauses.</span> -</span><span id="unalias_group-17"><a href="#unalias_group-17"><span class="linenos">17</span></a> -</span><span id="unalias_group-18"><a href="#unalias_group-18"><span class="linenos">18</span></a><span class="sd"> Example:</span> -</span><span id="unalias_group-19"><a href="#unalias_group-19"><span class="linenos">19</span></a><span class="sd"> >>> import sqlglot</span> -</span><span id="unalias_group-20"><a href="#unalias_group-20"><span class="linenos">20</span></a><span class="sd"> >>> sqlglot.parse_one("SELECT a AS b FROM x GROUP BY b").transform(unalias_group).sql()</span> -</span><span id="unalias_group-21"><a href="#unalias_group-21"><span class="linenos">21</span></a><span class="sd"> 'SELECT a AS b FROM x GROUP BY 1'</span> -</span><span id="unalias_group-22"><a href="#unalias_group-22"><span class="linenos">22</span></a> -</span><span id="unalias_group-23"><a href="#unalias_group-23"><span class="linenos">23</span></a><span class="sd"> Args:</span> -</span><span id="unalias_group-24"><a href="#unalias_group-24"><span class="linenos">24</span></a><span class="sd"> expression: the expression that will be transformed.</span> -</span><span id="unalias_group-25"><a href="#unalias_group-25"><span class="linenos">25</span></a> -</span><span id="unalias_group-26"><a href="#unalias_group-26"><span class="linenos">26</span></a><span class="sd"> Returns:</span> -</span><span id="unalias_group-27"><a href="#unalias_group-27"><span class="linenos">27</span></a><span class="sd"> The transformed expression.</span> -</span><span id="unalias_group-28"><a href="#unalias_group-28"><span class="linenos">28</span></a><span class="sd"> """</span> -</span><span id="unalias_group-29"><a href="#unalias_group-29"><span class="linenos">29</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">):</span> -</span><span id="unalias_group-30"><a href="#unalias_group-30"><span class="linenos">30</span></a> <span class="n">aliased_selects</span> <span class="o">=</span> <span class="p">{</span> -</span><span id="unalias_group-31"><a href="#unalias_group-31"><span class="linenos">31</span></a> <span class="n">e</span><span class="o">.</span><span class="n">alias</span><span class="p">:</span> <span class="n">i</span> -</span><span id="unalias_group-32"><a href="#unalias_group-32"><span class="linenos">32</span></a> <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">e</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="o">.</span><span class="n">expressions</span><span class="p">,</span> <span class="n">start</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span> -</span><span id="unalias_group-33"><a href="#unalias_group-33"><span class="linenos">33</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">e</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Alias</span><span class="p">)</span> -</span><span id="unalias_group-34"><a href="#unalias_group-34"><span class="linenos">34</span></a> <span class="p">}</span> -</span><span id="unalias_group-35"><a href="#unalias_group-35"><span class="linenos">35</span></a> -</span><span id="unalias_group-36"><a href="#unalias_group-36"><span class="linenos">36</span></a> <span class="k">for</span> <span class="n">group_by</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">expressions</span><span class="p">:</span> -</span><span id="unalias_group-37"><a href="#unalias_group-37"><span class="linenos">37</span></a> <span class="k">if</span> <span class="p">(</span> -</span><span id="unalias_group-38"><a href="#unalias_group-38"><span class="linenos">38</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">group_by</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)</span> -</span><span id="unalias_group-39"><a href="#unalias_group-39"><span class="linenos">39</span></a> <span class="ow">and</span> <span class="ow">not</span> <span class="n">group_by</span><span class="o">.</span><span class="n">table</span> -</span><span id="unalias_group-40"><a href="#unalias_group-40"><span class="linenos">40</span></a> <span class="ow">and</span> <span class="n">group_by</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">aliased_selects</span> -</span><span id="unalias_group-41"><a href="#unalias_group-41"><span class="linenos">41</span></a> <span class="p">):</span> -</span><span id="unalias_group-42"><a href="#unalias_group-42"><span class="linenos">42</span></a> <span class="n">group_by</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">Literal</span><span class="o">.</span><span class="n">number</span><span class="p">(</span><span class="n">aliased_selects</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">group_by</span><span class="o">.</span><span class="n">name</span><span class="p">)))</span> -</span><span id="unalias_group-43"><a href="#unalias_group-43"><span class="linenos">43</span></a> -</span><span id="unalias_group-44"><a href="#unalias_group-44"><span class="linenos">44</span></a> <span class="k">return</span> <span class="n">expression</span> + <div class="pdoc-code codehilite"><pre><span></span><span id="unalias_group-13"><a href="#unalias_group-13"><span class="linenos">13</span></a><span class="k">def</span> <span class="nf">unalias_group</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="unalias_group-14"><a href="#unalias_group-14"><span class="linenos">14</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="unalias_group-15"><a href="#unalias_group-15"><span class="linenos">15</span></a><span class="sd"> Replace references to select aliases in GROUP BY clauses.</span> +</span><span id="unalias_group-16"><a href="#unalias_group-16"><span class="linenos">16</span></a> +</span><span id="unalias_group-17"><a href="#unalias_group-17"><span class="linenos">17</span></a><span class="sd"> Example:</span> +</span><span id="unalias_group-18"><a href="#unalias_group-18"><span class="linenos">18</span></a><span class="sd"> >>> import sqlglot</span> +</span><span id="unalias_group-19"><a href="#unalias_group-19"><span class="linenos">19</span></a><span class="sd"> >>> sqlglot.parse_one("SELECT a AS b FROM x GROUP BY b").transform(unalias_group).sql()</span> +</span><span id="unalias_group-20"><a href="#unalias_group-20"><span class="linenos">20</span></a><span class="sd"> 'SELECT a AS b FROM x GROUP BY 1'</span> +</span><span id="unalias_group-21"><a href="#unalias_group-21"><span class="linenos">21</span></a> +</span><span id="unalias_group-22"><a href="#unalias_group-22"><span class="linenos">22</span></a><span class="sd"> Args:</span> +</span><span id="unalias_group-23"><a href="#unalias_group-23"><span class="linenos">23</span></a><span class="sd"> expression: the expression that will be transformed.</span> +</span><span id="unalias_group-24"><a href="#unalias_group-24"><span class="linenos">24</span></a> +</span><span id="unalias_group-25"><a href="#unalias_group-25"><span class="linenos">25</span></a><span class="sd"> Returns:</span> +</span><span id="unalias_group-26"><a href="#unalias_group-26"><span class="linenos">26</span></a><span class="sd"> The transformed expression.</span> +</span><span id="unalias_group-27"><a href="#unalias_group-27"><span class="linenos">27</span></a><span class="sd"> """</span> +</span><span id="unalias_group-28"><a href="#unalias_group-28"><span class="linenos">28</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Group</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">):</span> +</span><span id="unalias_group-29"><a href="#unalias_group-29"><span class="linenos">29</span></a> <span class="n">aliased_selects</span> <span class="o">=</span> <span class="p">{</span> +</span><span id="unalias_group-30"><a href="#unalias_group-30"><span class="linenos">30</span></a> <span class="n">e</span><span class="o">.</span><span class="n">alias</span><span class="p">:</span> <span class="n">i</span> +</span><span id="unalias_group-31"><a href="#unalias_group-31"><span class="linenos">31</span></a> <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">e</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">parent</span><span class="o">.</span><span class="n">expressions</span><span class="p">,</span> <span class="n">start</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span> +</span><span id="unalias_group-32"><a href="#unalias_group-32"><span class="linenos">32</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">e</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Alias</span><span class="p">)</span> +</span><span id="unalias_group-33"><a href="#unalias_group-33"><span class="linenos">33</span></a> <span class="p">}</span> +</span><span id="unalias_group-34"><a href="#unalias_group-34"><span class="linenos">34</span></a> +</span><span id="unalias_group-35"><a href="#unalias_group-35"><span class="linenos">35</span></a> <span class="k">for</span> <span class="n">group_by</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">expressions</span><span class="p">:</span> +</span><span id="unalias_group-36"><a href="#unalias_group-36"><span class="linenos">36</span></a> <span class="k">if</span> <span class="p">(</span> +</span><span id="unalias_group-37"><a href="#unalias_group-37"><span class="linenos">37</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">group_by</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)</span> +</span><span id="unalias_group-38"><a href="#unalias_group-38"><span class="linenos">38</span></a> <span class="ow">and</span> <span class="ow">not</span> <span class="n">group_by</span><span class="o">.</span><span class="n">table</span> +</span><span id="unalias_group-39"><a href="#unalias_group-39"><span class="linenos">39</span></a> <span class="ow">and</span> <span class="n">group_by</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">aliased_selects</span> +</span><span id="unalias_group-40"><a href="#unalias_group-40"><span class="linenos">40</span></a> <span class="p">):</span> +</span><span id="unalias_group-41"><a href="#unalias_group-41"><span class="linenos">41</span></a> <span class="n">group_by</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">Literal</span><span class="o">.</span><span class="n">number</span><span class="p">(</span><span class="n">aliased_selects</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">group_by</span><span class="o">.</span><span class="n">name</span><span class="p">)))</span> +</span><span id="unalias_group-42"><a href="#unalias_group-42"><span class="linenos">42</span></a> +</span><span id="unalias_group-43"><a href="#unalias_group-43"><span class="linenos">43</span></a> <span class="k">return</span> <span class="n">expression</span> </span></pre></div> @@ -300,40 +337,38 @@ </div> <a class="headerlink" href="#eliminate_distinct_on"></a> - <div class="pdoc-code codehilite"><pre><span></span><span id="eliminate_distinct_on-47"><a href="#eliminate_distinct_on-47"><span class="linenos">47</span></a><span class="k">def</span> <span class="nf">eliminate_distinct_on</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="eliminate_distinct_on-48"><a href="#eliminate_distinct_on-48"><span class="linenos">48</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="eliminate_distinct_on-49"><a href="#eliminate_distinct_on-49"><span class="linenos">49</span></a><span class="sd"> Convert SELECT DISTINCT ON statements to a subquery with a window function.</span> -</span><span id="eliminate_distinct_on-50"><a href="#eliminate_distinct_on-50"><span class="linenos">50</span></a> -</span><span id="eliminate_distinct_on-51"><a href="#eliminate_distinct_on-51"><span class="linenos">51</span></a><span class="sd"> This is useful for dialects that don't support SELECT DISTINCT ON but support window functions.</span> -</span><span id="eliminate_distinct_on-52"><a href="#eliminate_distinct_on-52"><span class="linenos">52</span></a> -</span><span id="eliminate_distinct_on-53"><a href="#eliminate_distinct_on-53"><span class="linenos">53</span></a><span class="sd"> Args:</span> -</span><span id="eliminate_distinct_on-54"><a href="#eliminate_distinct_on-54"><span class="linenos">54</span></a><span class="sd"> expression: the expression that will be transformed.</span> -</span><span id="eliminate_distinct_on-55"><a href="#eliminate_distinct_on-55"><span class="linenos">55</span></a> -</span><span id="eliminate_distinct_on-56"><a href="#eliminate_distinct_on-56"><span class="linenos">56</span></a><span class="sd"> Returns:</span> -</span><span id="eliminate_distinct_on-57"><a href="#eliminate_distinct_on-57"><span class="linenos">57</span></a><span class="sd"> The transformed expression.</span> -</span><span id="eliminate_distinct_on-58"><a href="#eliminate_distinct_on-58"><span class="linenos">58</span></a><span class="sd"> """</span> -</span><span id="eliminate_distinct_on-59"><a href="#eliminate_distinct_on-59"><span class="linenos">59</span></a> <span class="k">if</span> <span class="p">(</span> -</span><span id="eliminate_distinct_on-60"><a href="#eliminate_distinct_on-60"><span class="linenos">60</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-61"><a href="#eliminate_distinct_on-61"><span class="linenos">61</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"distinct"</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-62"><a href="#eliminate_distinct_on-62"><span class="linenos">62</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"on"</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-63"><a href="#eliminate_distinct_on-63"><span class="linenos">63</span></a> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Tuple</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-64"><a href="#eliminate_distinct_on-64"><span class="linenos">64</span></a> <span class="p">):</span> -</span><span id="eliminate_distinct_on-65"><a href="#eliminate_distinct_on-65"><span class="linenos">65</span></a> <span class="n">distinct_cols</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">]</span><span class="o">.</span><span class="n">expressions</span> -</span><span id="eliminate_distinct_on-66"><a href="#eliminate_distinct_on-66"><span class="linenos">66</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span> -</span><span id="eliminate_distinct_on-67"><a href="#eliminate_distinct_on-67"><span class="linenos">67</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span> -</span><span id="eliminate_distinct_on-68"><a href="#eliminate_distinct_on-68"><span class="linenos">68</span></a> <span class="n">row_number</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_row_number"</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-69"><a href="#eliminate_distinct_on-69"><span class="linenos">69</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">(</span> -</span><span id="eliminate_distinct_on-70"><a href="#eliminate_distinct_on-70"><span class="linenos">70</span></a> <span class="n">this</span><span class="o">=</span><span class="n">exp</span><span class="o">.</span><span class="n">RowNumber</span><span class="p">(),</span> -</span><span id="eliminate_distinct_on-71"><a href="#eliminate_distinct_on-71"><span class="linenos">71</span></a> <span class="n">partition_by</span><span class="o">=</span><span class="n">distinct_cols</span><span class="p">,</span> -</span><span id="eliminate_distinct_on-72"><a href="#eliminate_distinct_on-72"><span class="linenos">72</span></a> <span class="p">)</span> -</span><span id="eliminate_distinct_on-73"><a href="#eliminate_distinct_on-73"><span class="linenos">73</span></a> <span class="n">order</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"order"</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-74"><a href="#eliminate_distinct_on-74"><span class="linenos">74</span></a> <span class="k">if</span> <span class="n">order</span><span class="p">:</span> -</span><span id="eliminate_distinct_on-75"><a href="#eliminate_distinct_on-75"><span class="linenos">75</span></a> <span class="n">window</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="s2">"order"</span><span class="p">,</span> <span class="n">order</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> -</span><span id="eliminate_distinct_on-76"><a href="#eliminate_distinct_on-76"><span class="linenos">76</span></a> <span class="n">order</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span> -</span><span id="eliminate_distinct_on-77"><a href="#eliminate_distinct_on-77"><span class="linenos">77</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">row_number</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-78"><a href="#eliminate_distinct_on-78"><span class="linenos">78</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-79"><a href="#eliminate_distinct_on-79"><span class="linenos">79</span></a> <span class="k">return</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="n">outer_selects</span><span class="p">)</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">())</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="sa">f</span><span class="s1">'"</span><span class="si">{</span><span class="n">row_number</span><span class="si">}</span><span class="s1">" = 1'</span><span class="p">)</span> -</span><span id="eliminate_distinct_on-80"><a href="#eliminate_distinct_on-80"><span class="linenos">80</span></a> <span class="k">return</span> <span class="n">expression</span> + <div class="pdoc-code codehilite"><pre><span></span><span id="eliminate_distinct_on-46"><a href="#eliminate_distinct_on-46"><span class="linenos">46</span></a><span class="k">def</span> <span class="nf">eliminate_distinct_on</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="eliminate_distinct_on-47"><a href="#eliminate_distinct_on-47"><span class="linenos">47</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="eliminate_distinct_on-48"><a href="#eliminate_distinct_on-48"><span class="linenos">48</span></a><span class="sd"> Convert SELECT DISTINCT ON statements to a subquery with a window function.</span> +</span><span id="eliminate_distinct_on-49"><a href="#eliminate_distinct_on-49"><span class="linenos">49</span></a> +</span><span id="eliminate_distinct_on-50"><a href="#eliminate_distinct_on-50"><span class="linenos">50</span></a><span class="sd"> This is useful for dialects that don't support SELECT DISTINCT ON but support window functions.</span> +</span><span id="eliminate_distinct_on-51"><a href="#eliminate_distinct_on-51"><span class="linenos">51</span></a> +</span><span id="eliminate_distinct_on-52"><a href="#eliminate_distinct_on-52"><span class="linenos">52</span></a><span class="sd"> Args:</span> +</span><span id="eliminate_distinct_on-53"><a href="#eliminate_distinct_on-53"><span class="linenos">53</span></a><span class="sd"> expression: the expression that will be transformed.</span> +</span><span id="eliminate_distinct_on-54"><a href="#eliminate_distinct_on-54"><span class="linenos">54</span></a> +</span><span id="eliminate_distinct_on-55"><a href="#eliminate_distinct_on-55"><span class="linenos">55</span></a><span class="sd"> Returns:</span> +</span><span id="eliminate_distinct_on-56"><a href="#eliminate_distinct_on-56"><span class="linenos">56</span></a><span class="sd"> The transformed expression.</span> +</span><span id="eliminate_distinct_on-57"><a href="#eliminate_distinct_on-57"><span class="linenos">57</span></a><span class="sd"> """</span> +</span><span id="eliminate_distinct_on-58"><a href="#eliminate_distinct_on-58"><span class="linenos">58</span></a> <span class="k">if</span> <span class="p">(</span> +</span><span id="eliminate_distinct_on-59"><a href="#eliminate_distinct_on-59"><span class="linenos">59</span></a> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-60"><a href="#eliminate_distinct_on-60"><span class="linenos">60</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"distinct"</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-61"><a href="#eliminate_distinct_on-61"><span class="linenos">61</span></a> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"on"</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-62"><a href="#eliminate_distinct_on-62"><span class="linenos">62</span></a> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Tuple</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-63"><a href="#eliminate_distinct_on-63"><span class="linenos">63</span></a> <span class="p">):</span> +</span><span id="eliminate_distinct_on-64"><a href="#eliminate_distinct_on-64"><span class="linenos">64</span></a> <span class="n">distinct_cols</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"distinct"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"on"</span><span class="p">]</span><span class="o">.</span><span class="n">expressions</span> +</span><span id="eliminate_distinct_on-65"><a href="#eliminate_distinct_on-65"><span class="linenos">65</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span> +</span><span id="eliminate_distinct_on-66"><a href="#eliminate_distinct_on-66"><span class="linenos">66</span></a> <span class="n">row_number</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_row_number"</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-67"><a href="#eliminate_distinct_on-67"><span class="linenos">67</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">(</span> +</span><span id="eliminate_distinct_on-68"><a href="#eliminate_distinct_on-68"><span class="linenos">68</span></a> <span class="n">this</span><span class="o">=</span><span class="n">exp</span><span class="o">.</span><span class="n">RowNumber</span><span class="p">(),</span> +</span><span id="eliminate_distinct_on-69"><a href="#eliminate_distinct_on-69"><span class="linenos">69</span></a> <span class="n">partition_by</span><span class="o">=</span><span class="n">distinct_cols</span><span class="p">,</span> +</span><span id="eliminate_distinct_on-70"><a href="#eliminate_distinct_on-70"><span class="linenos">70</span></a> <span class="p">)</span> +</span><span id="eliminate_distinct_on-71"><a href="#eliminate_distinct_on-71"><span class="linenos">71</span></a> <span class="n">order</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"order"</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-72"><a href="#eliminate_distinct_on-72"><span class="linenos">72</span></a> <span class="k">if</span> <span class="n">order</span><span class="p">:</span> +</span><span id="eliminate_distinct_on-73"><a href="#eliminate_distinct_on-73"><span class="linenos">73</span></a> <span class="n">window</span><span class="o">.</span><span class="n">set</span><span class="p">(</span><span class="s2">"order"</span><span class="p">,</span> <span class="n">order</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> +</span><span id="eliminate_distinct_on-74"><a href="#eliminate_distinct_on-74"><span class="linenos">74</span></a> <span class="n">window</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">row_number</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-75"><a href="#eliminate_distinct_on-75"><span class="linenos">75</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">window</span><span class="p">,</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-76"><a href="#eliminate_distinct_on-76"><span class="linenos">76</span></a> <span class="k">return</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="n">outer_selects</span><span class="p">)</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">())</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="sa">f</span><span class="s1">'"</span><span class="si">{</span><span class="n">row_number</span><span class="si">}</span><span class="s1">" = 1'</span><span class="p">)</span> +</span><span id="eliminate_distinct_on-77"><a href="#eliminate_distinct_on-77"><span class="linenos">77</span></a> <span class="k">return</span> <span class="n">expression</span> </span></pre></div> @@ -356,6 +391,67 @@ </section> + <section id="eliminate_qualify"> + <input id="eliminate_qualify-view-source" class="view-source-toggle-state" type="checkbox" aria-hidden="true" tabindex="-1"> +<div class="attr function"> + + <span class="def">def</span> + <span class="name">eliminate_qualify</span><span class="signature pdoc-code multiline">(<span class="param"> <span class="n">expression</span><span class="p">:</span> <span class="n"><a href="expressions.html#Expression">sqlglot.expressions.Expression</a></span></span><span class="return-annotation">) -> <span class="n"><a href="expressions.html#Expression">sqlglot.expressions.Expression</a></span>:</span></span> + + <label class="view-source-button" for="eliminate_qualify-view-source"><span>View Source</span></label> + + </div> + <a class="headerlink" href="#eliminate_qualify"></a> + <div class="pdoc-code codehilite"><pre><span></span><span id="eliminate_qualify-80"><a href="#eliminate_qualify-80"><span class="linenos"> 80</span></a><span class="k">def</span> <span class="nf">eliminate_qualify</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="eliminate_qualify-81"><a href="#eliminate_qualify-81"><span class="linenos"> 81</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="eliminate_qualify-82"><a href="#eliminate_qualify-82"><span class="linenos"> 82</span></a><span class="sd"> Convert SELECT statements that contain the QUALIFY clause into subqueries, filtered equivalently.</span> +</span><span id="eliminate_qualify-83"><a href="#eliminate_qualify-83"><span class="linenos"> 83</span></a> +</span><span id="eliminate_qualify-84"><a href="#eliminate_qualify-84"><span class="linenos"> 84</span></a><span class="sd"> The idea behind this transformation can be seen in Snowflake's documentation for QUALIFY:</span> +</span><span id="eliminate_qualify-85"><a href="#eliminate_qualify-85"><span class="linenos"> 85</span></a><span class="sd"> https://docs.snowflake.com/en/sql-reference/constructs/qualify</span> +</span><span id="eliminate_qualify-86"><a href="#eliminate_qualify-86"><span class="linenos"> 86</span></a> +</span><span id="eliminate_qualify-87"><a href="#eliminate_qualify-87"><span class="linenos"> 87</span></a><span class="sd"> Some dialects don't support window functions in the WHERE clause, so we need to include them as</span> +</span><span id="eliminate_qualify-88"><a href="#eliminate_qualify-88"><span class="linenos"> 88</span></a><span class="sd"> projections in the subquery, in order to refer to them in the outer filter using aliases. Also,</span> +</span><span id="eliminate_qualify-89"><a href="#eliminate_qualify-89"><span class="linenos"> 89</span></a><span class="sd"> if a column is referenced in the QUALIFY clause but is not selected, we need to include it too,</span> +</span><span id="eliminate_qualify-90"><a href="#eliminate_qualify-90"><span class="linenos"> 90</span></a><span class="sd"> otherwise we won't be able to refer to it in the outer query's WHERE clause.</span> +</span><span id="eliminate_qualify-91"><a href="#eliminate_qualify-91"><span class="linenos"> 91</span></a><span class="sd"> """</span> +</span><span id="eliminate_qualify-92"><a href="#eliminate_qualify-92"><span class="linenos"> 92</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Select</span><span class="p">)</span> <span class="ow">and</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"qualify"</span><span class="p">):</span> +</span><span id="eliminate_qualify-93"><a href="#eliminate_qualify-93"><span class="linenos"> 93</span></a> <span class="n">taken</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">)</span> +</span><span id="eliminate_qualify-94"><a href="#eliminate_qualify-94"><span class="linenos"> 94</span></a> <span class="k">for</span> <span class="n">select</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span><span class="p">:</span> +</span><span id="eliminate_qualify-95"><a href="#eliminate_qualify-95"><span class="linenos"> 95</span></a> <span class="k">if</span> <span class="ow">not</span> <span class="n">select</span><span class="o">.</span><span class="n">alias_or_name</span><span class="p">:</span> +</span><span id="eliminate_qualify-96"><a href="#eliminate_qualify-96"><span class="linenos"> 96</span></a> <span class="n">alias</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">taken</span><span class="p">,</span> <span class="s2">"_c"</span><span class="p">)</span> +</span><span id="eliminate_qualify-97"><a href="#eliminate_qualify-97"><span class="linenos"> 97</span></a> <span class="n">select</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">select</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">alias</span><span class="p">))</span> +</span><span id="eliminate_qualify-98"><a href="#eliminate_qualify-98"><span class="linenos"> 98</span></a> <span class="n">taken</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">alias</span><span class="p">)</span> +</span><span id="eliminate_qualify-99"><a href="#eliminate_qualify-99"><span class="linenos"> 99</span></a> +</span><span id="eliminate_qualify-100"><a href="#eliminate_qualify-100"><span class="linenos">100</span></a> <span class="n">outer_selects</span> <span class="o">=</span> <span class="n">exp</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="o">*</span><span class="p">[</span><span class="n">select</span><span class="o">.</span><span class="n">alias_or_name</span> <span class="k">for</span> <span class="n">select</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">selects</span><span class="p">])</span> +</span><span id="eliminate_qualify-101"><a href="#eliminate_qualify-101"><span class="linenos">101</span></a> <span class="n">qualify_filters</span> <span class="o">=</span> <span class="n">expression</span><span class="o">.</span><span class="n">args</span><span class="p">[</span><span class="s2">"qualify"</span><span class="p">]</span><span class="o">.</span><span class="n">pop</span><span class="p">()</span><span class="o">.</span><span class="n">this</span> +</span><span id="eliminate_qualify-102"><a href="#eliminate_qualify-102"><span class="linenos">102</span></a> +</span><span id="eliminate_qualify-103"><a href="#eliminate_qualify-103"><span class="linenos">103</span></a> <span class="k">for</span> <span class="n">expr</span> <span class="ow">in</span> <span class="n">qualify_filters</span><span class="o">.</span><span class="n">find_all</span><span class="p">((</span><span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Column</span><span class="p">)):</span> +</span><span id="eliminate_qualify-104"><a href="#eliminate_qualify-104"><span class="linenos">104</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">expr</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Window</span><span class="p">):</span> +</span><span id="eliminate_qualify-105"><a href="#eliminate_qualify-105"><span class="linenos">105</span></a> <span class="n">alias</span> <span class="o">=</span> <span class="n">find_new_name</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">,</span> <span class="s2">"_w"</span><span class="p">)</span> +</span><span id="eliminate_qualify-106"><a href="#eliminate_qualify-106"><span class="linenos">106</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">alias_</span><span class="p">(</span><span class="n">expr</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">alias</span><span class="p">),</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="eliminate_qualify-107"><a href="#eliminate_qualify-107"><span class="linenos">107</span></a> <span class="n">expr</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">exp</span><span class="o">.</span><span class="n">column</span><span class="p">(</span><span class="n">alias</span><span class="p">))</span> +</span><span id="eliminate_qualify-108"><a href="#eliminate_qualify-108"><span class="linenos">108</span></a> <span class="k">elif</span> <span class="n">expr</span><span class="o">.</span><span class="n">name</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">expression</span><span class="o">.</span><span class="n">named_selects</span><span class="p">:</span> +</span><span id="eliminate_qualify-109"><a href="#eliminate_qualify-109"><span class="linenos">109</span></a> <span class="n">expression</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">expr</span><span class="o">.</span><span class="n">copy</span><span class="p">(),</span> <span class="n">copy</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> +</span><span id="eliminate_qualify-110"><a href="#eliminate_qualify-110"><span class="linenos">110</span></a> +</span><span id="eliminate_qualify-111"><a href="#eliminate_qualify-111"><span class="linenos">111</span></a> <span class="k">return</span> <span class="n">outer_selects</span><span class="o">.</span><span class="n">from_</span><span class="p">(</span><span class="n">expression</span><span class="o">.</span><span class="n">subquery</span><span class="p">(</span><span class="n">alias</span><span class="o">=</span><span class="s2">"_t"</span><span class="p">))</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">qualify_filters</span><span class="p">)</span> +</span><span id="eliminate_qualify-112"><a href="#eliminate_qualify-112"><span class="linenos">112</span></a> +</span><span id="eliminate_qualify-113"><a href="#eliminate_qualify-113"><span class="linenos">113</span></a> <span class="k">return</span> <span class="n">expression</span> +</span></pre></div> + + + <div class="docstring"><p>Convert SELECT statements that contain the QUALIFY clause into subqueries, filtered equivalently.</p> + +<p>The idea behind this transformation can be seen in Snowflake's documentation for QUALIFY: +<a href="https://docs.snowflake.com/en/sql-reference/constructs/qualify">https://docs.snowflake.com/en/sql-reference/constructs/qualify</a></p> + +<p>Some dialects don't support window functions in the WHERE clause, so we need to include them as +projections in the subquery, in order to refer to them in the outer filter using aliases. Also, +if a column is referenced in the QUALIFY clause but is not selected, we need to include it too, +otherwise we won't be able to refer to it in the outer query's WHERE clause.</p> +</div> + + + </section> <section id="remove_precision_parameterized_types"> <input id="remove_precision_parameterized_types-view-source" class="view-source-toggle-state" type="checkbox" aria-hidden="true" tabindex="-1"> <div class="attr function"> @@ -367,25 +463,25 @@ </div> <a class="headerlink" href="#remove_precision_parameterized_types"></a> - <div class="pdoc-code codehilite"><pre><span></span><span id="remove_precision_parameterized_types-83"><a href="#remove_precision_parameterized_types-83"><span class="linenos"> 83</span></a><span class="k">def</span> <span class="nf">remove_precision_parameterized_types</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> -</span><span id="remove_precision_parameterized_types-84"><a href="#remove_precision_parameterized_types-84"><span class="linenos"> 84</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="remove_precision_parameterized_types-85"><a href="#remove_precision_parameterized_types-85"><span class="linenos"> 85</span></a><span class="sd"> Some dialects only allow the precision for parameterized types to be defined in the DDL and not in other expressions.</span> -</span><span id="remove_precision_parameterized_types-86"><a href="#remove_precision_parameterized_types-86"><span class="linenos"> 86</span></a><span class="sd"> This transforms removes the precision from parameterized types in expressions.</span> -</span><span id="remove_precision_parameterized_types-87"><a href="#remove_precision_parameterized_types-87"><span class="linenos"> 87</span></a><span class="sd"> """</span> -</span><span id="remove_precision_parameterized_types-88"><a href="#remove_precision_parameterized_types-88"><span class="linenos"> 88</span></a> <span class="k">return</span> <span class="n">expression</span><span class="o">.</span><span class="n">transform</span><span class="p">(</span> -</span><span id="remove_precision_parameterized_types-89"><a href="#remove_precision_parameterized_types-89"><span class="linenos"> 89</span></a> <span class="k">lambda</span> <span class="n">node</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">(</span> -</span><span id="remove_precision_parameterized_types-90"><a href="#remove_precision_parameterized_types-90"><span class="linenos"> 90</span></a> <span class="o">**</span><span class="p">{</span> -</span><span id="remove_precision_parameterized_types-91"><a href="#remove_precision_parameterized_types-91"><span class="linenos"> 91</span></a> <span class="o">**</span><span class="n">node</span><span class="o">.</span><span class="n">args</span><span class="p">,</span> -</span><span id="remove_precision_parameterized_types-92"><a href="#remove_precision_parameterized_types-92"><span class="linenos"> 92</span></a> <span class="s2">"expressions"</span><span class="p">:</span> <span class="p">[</span> -</span><span id="remove_precision_parameterized_types-93"><a href="#remove_precision_parameterized_types-93"><span class="linenos"> 93</span></a> <span class="n">node_expression</span> -</span><span id="remove_precision_parameterized_types-94"><a href="#remove_precision_parameterized_types-94"><span class="linenos"> 94</span></a> <span class="k">for</span> <span class="n">node_expression</span> <span class="ow">in</span> <span class="n">node</span><span class="o">.</span><span class="n">expressions</span> -</span><span id="remove_precision_parameterized_types-95"><a href="#remove_precision_parameterized_types-95"><span class="linenos"> 95</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node_expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> -</span><span id="remove_precision_parameterized_types-96"><a href="#remove_precision_parameterized_types-96"><span class="linenos"> 96</span></a> <span class="p">],</span> -</span><span id="remove_precision_parameterized_types-97"><a href="#remove_precision_parameterized_types-97"><span class="linenos"> 97</span></a> <span class="p">}</span> -</span><span id="remove_precision_parameterized_types-98"><a href="#remove_precision_parameterized_types-98"><span class="linenos"> 98</span></a> <span class="p">)</span> -</span><span id="remove_precision_parameterized_types-99"><a href="#remove_precision_parameterized_types-99"><span class="linenos"> 99</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> -</span><span id="remove_precision_parameterized_types-100"><a href="#remove_precision_parameterized_types-100"><span class="linenos">100</span></a> <span class="k">else</span> <span class="n">node</span><span class="p">,</span> -</span><span id="remove_precision_parameterized_types-101"><a href="#remove_precision_parameterized_types-101"><span class="linenos">101</span></a> <span class="p">)</span> + <div class="pdoc-code codehilite"><pre><span></span><span id="remove_precision_parameterized_types-116"><a href="#remove_precision_parameterized_types-116"><span class="linenos">116</span></a><span class="k">def</span> <span class="nf">remove_precision_parameterized_types</span><span class="p">(</span><span class="n">expression</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">)</span> <span class="o">-></span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">:</span> +</span><span id="remove_precision_parameterized_types-117"><a href="#remove_precision_parameterized_types-117"><span class="linenos">117</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="remove_precision_parameterized_types-118"><a href="#remove_precision_parameterized_types-118"><span class="linenos">118</span></a><span class="sd"> Some dialects only allow the precision for parameterized types to be defined in the DDL and not in other expressions.</span> +</span><span id="remove_precision_parameterized_types-119"><a href="#remove_precision_parameterized_types-119"><span class="linenos">119</span></a><span class="sd"> This transforms removes the precision from parameterized types in expressions.</span> +</span><span id="remove_precision_parameterized_types-120"><a href="#remove_precision_parameterized_types-120"><span class="linenos">120</span></a><span class="sd"> """</span> +</span><span id="remove_precision_parameterized_types-121"><a href="#remove_precision_parameterized_types-121"><span class="linenos">121</span></a> <span class="k">return</span> <span class="n">expression</span><span class="o">.</span><span class="n">transform</span><span class="p">(</span> +</span><span id="remove_precision_parameterized_types-122"><a href="#remove_precision_parameterized_types-122"><span class="linenos">122</span></a> <span class="k">lambda</span> <span class="n">node</span><span class="p">:</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">(</span> +</span><span id="remove_precision_parameterized_types-123"><a href="#remove_precision_parameterized_types-123"><span class="linenos">123</span></a> <span class="o">**</span><span class="p">{</span> +</span><span id="remove_precision_parameterized_types-124"><a href="#remove_precision_parameterized_types-124"><span class="linenos">124</span></a> <span class="o">**</span><span class="n">node</span><span class="o">.</span><span class="n">args</span><span class="p">,</span> +</span><span id="remove_precision_parameterized_types-125"><a href="#remove_precision_parameterized_types-125"><span class="linenos">125</span></a> <span class="s2">"expressions"</span><span class="p">:</span> <span class="p">[</span> +</span><span id="remove_precision_parameterized_types-126"><a href="#remove_precision_parameterized_types-126"><span class="linenos">126</span></a> <span class="n">node_expression</span> +</span><span id="remove_precision_parameterized_types-127"><a href="#remove_precision_parameterized_types-127"><span class="linenos">127</span></a> <span class="k">for</span> <span class="n">node_expression</span> <span class="ow">in</span> <span class="n">node</span><span class="o">.</span><span class="n">expressions</span> +</span><span id="remove_precision_parameterized_types-128"><a href="#remove_precision_parameterized_types-128"><span class="linenos">128</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node_expression</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> +</span><span id="remove_precision_parameterized_types-129"><a href="#remove_precision_parameterized_types-129"><span class="linenos">129</span></a> <span class="p">],</span> +</span><span id="remove_precision_parameterized_types-130"><a href="#remove_precision_parameterized_types-130"><span class="linenos">130</span></a> <span class="p">}</span> +</span><span id="remove_precision_parameterized_types-131"><a href="#remove_precision_parameterized_types-131"><span class="linenos">131</span></a> <span class="p">)</span> +</span><span id="remove_precision_parameterized_types-132"><a href="#remove_precision_parameterized_types-132"><span class="linenos">132</span></a> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">node</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">DataType</span><span class="p">)</span> +</span><span id="remove_precision_parameterized_types-133"><a href="#remove_precision_parameterized_types-133"><span class="linenos">133</span></a> <span class="k">else</span> <span class="n">node</span><span class="p">,</span> +</span><span id="remove_precision_parameterized_types-134"><a href="#remove_precision_parameterized_types-134"><span class="linenos">134</span></a> <span class="p">)</span> </span></pre></div> @@ -406,29 +502,29 @@ This transforms removes the precision from parameterized types in expressions.</ </div> <a class="headerlink" href="#preprocess"></a> - <div class="pdoc-code codehilite"><pre><span></span><span id="preprocess-104"><a href="#preprocess-104"><span class="linenos">104</span></a><span class="k">def</span> <span class="nf">preprocess</span><span class="p">(</span> -</span><span id="preprocess-105"><a href="#preprocess-105"><span class="linenos">105</span></a> <span class="n">transforms</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">List</span><span class="p">[</span><span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">]],</span> -</span><span id="preprocess-106"><a href="#preprocess-106"><span class="linenos">106</span></a> <span class="n">to_sql</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">],</span> -</span><span id="preprocess-107"><a href="#preprocess-107"><span class="linenos">107</span></a><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">]:</span> -</span><span id="preprocess-108"><a href="#preprocess-108"><span class="linenos">108</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="preprocess-109"><a href="#preprocess-109"><span class="linenos">109</span></a><span class="sd"> Creates a new transform by chaining a sequence of transformations and converts the resulting</span> -</span><span id="preprocess-110"><a href="#preprocess-110"><span class="linenos">110</span></a><span class="sd"> expression to SQL, using an appropriate `Generator.TRANSFORMS` function.</span> -</span><span id="preprocess-111"><a href="#preprocess-111"><span class="linenos">111</span></a> -</span><span id="preprocess-112"><a href="#preprocess-112"><span class="linenos">112</span></a><span class="sd"> Args:</span> -</span><span id="preprocess-113"><a href="#preprocess-113"><span class="linenos">113</span></a><span class="sd"> transforms: sequence of transform functions. These will be called in order.</span> -</span><span id="preprocess-114"><a href="#preprocess-114"><span class="linenos">114</span></a><span class="sd"> to_sql: final transform that converts the resulting expression to a SQL string.</span> -</span><span id="preprocess-115"><a href="#preprocess-115"><span class="linenos">115</span></a> -</span><span id="preprocess-116"><a href="#preprocess-116"><span class="linenos">116</span></a><span class="sd"> Returns:</span> -</span><span id="preprocess-117"><a href="#preprocess-117"><span class="linenos">117</span></a><span class="sd"> Function that can be used as a generator transform.</span> -</span><span id="preprocess-118"><a href="#preprocess-118"><span class="linenos">118</span></a><span class="sd"> """</span> -</span><span id="preprocess-119"><a href="#preprocess-119"><span class="linenos">119</span></a> -</span><span id="preprocess-120"><a href="#preprocess-120"><span class="linenos">120</span></a> <span class="k">def</span> <span class="nf">_to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">):</span> -</span><span id="preprocess-121"><a href="#preprocess-121"><span class="linenos">121</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">0</span><span class="p">](</span><span class="n">expression</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> -</span><span id="preprocess-122"><a href="#preprocess-122"><span class="linenos">122</span></a> <span class="k">for</span> <span class="n">t</span> <span class="ow">in</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">1</span><span class="p">:]:</span> -</span><span id="preprocess-123"><a href="#preprocess-123"><span class="linenos">123</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">t</span><span class="p">(</span><span class="n">expression</span><span class="p">)</span> -</span><span id="preprocess-124"><a href="#preprocess-124"><span class="linenos">124</span></a> <span class="k">return</span> <span class="n">to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">)</span> -</span><span id="preprocess-125"><a href="#preprocess-125"><span class="linenos">125</span></a> -</span><span id="preprocess-126"><a href="#preprocess-126"><span class="linenos">126</span></a> <span class="k">return</span> <span class="n">_to_sql</span> + <div class="pdoc-code codehilite"><pre><span></span><span id="preprocess-137"><a href="#preprocess-137"><span class="linenos">137</span></a><span class="k">def</span> <span class="nf">preprocess</span><span class="p">(</span> +</span><span id="preprocess-138"><a href="#preprocess-138"><span class="linenos">138</span></a> <span class="n">transforms</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">List</span><span class="p">[</span><span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">]],</span> +</span><span id="preprocess-139"><a href="#preprocess-139"><span class="linenos">139</span></a> <span class="n">to_sql</span><span class="p">:</span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">],</span> +</span><span id="preprocess-140"><a href="#preprocess-140"><span class="linenos">140</span></a><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">[[</span><span class="n">Generator</span><span class="p">,</span> <span class="n">exp</span><span class="o">.</span><span class="n">Expression</span><span class="p">],</span> <span class="nb">str</span><span class="p">]:</span> +</span><span id="preprocess-141"><a href="#preprocess-141"><span class="linenos">141</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="preprocess-142"><a href="#preprocess-142"><span class="linenos">142</span></a><span class="sd"> Creates a new transform by chaining a sequence of transformations and converts the resulting</span> +</span><span id="preprocess-143"><a href="#preprocess-143"><span class="linenos">143</span></a><span class="sd"> expression to SQL, using an appropriate `Generator.TRANSFORMS` function.</span> +</span><span id="preprocess-144"><a href="#preprocess-144"><span class="linenos">144</span></a> +</span><span id="preprocess-145"><a href="#preprocess-145"><span class="linenos">145</span></a><span class="sd"> Args:</span> +</span><span id="preprocess-146"><a href="#preprocess-146"><span class="linenos">146</span></a><span class="sd"> transforms: sequence of transform functions. These will be called in order.</span> +</span><span id="preprocess-147"><a href="#preprocess-147"><span class="linenos">147</span></a><span class="sd"> to_sql: final transform that converts the resulting expression to a SQL string.</span> +</span><span id="preprocess-148"><a href="#preprocess-148"><span class="linenos">148</span></a> +</span><span id="preprocess-149"><a href="#preprocess-149"><span class="linenos">149</span></a><span class="sd"> Returns:</span> +</span><span id="preprocess-150"><a href="#preprocess-150"><span class="linenos">150</span></a><span class="sd"> Function that can be used as a generator transform.</span> +</span><span id="preprocess-151"><a href="#preprocess-151"><span class="linenos">151</span></a><span class="sd"> """</span> +</span><span id="preprocess-152"><a href="#preprocess-152"><span class="linenos">152</span></a> +</span><span id="preprocess-153"><a href="#preprocess-153"><span class="linenos">153</span></a> <span class="k">def</span> <span class="nf">_to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">):</span> +</span><span id="preprocess-154"><a href="#preprocess-154"><span class="linenos">154</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">0</span><span class="p">](</span><span class="n">expression</span><span class="o">.</span><span class="n">copy</span><span class="p">())</span> +</span><span id="preprocess-155"><a href="#preprocess-155"><span class="linenos">155</span></a> <span class="k">for</span> <span class="n">t</span> <span class="ow">in</span> <span class="n">transforms</span><span class="p">[</span><span class="mi">1</span><span class="p">:]:</span> +</span><span id="preprocess-156"><a href="#preprocess-156"><span class="linenos">156</span></a> <span class="n">expression</span> <span class="o">=</span> <span class="n">t</span><span class="p">(</span><span class="n">expression</span><span class="p">)</span> +</span><span id="preprocess-157"><a href="#preprocess-157"><span class="linenos">157</span></a> <span class="k">return</span> <span class="n">to_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">expression</span><span class="p">)</span> +</span><span id="preprocess-158"><a href="#preprocess-158"><span class="linenos">158</span></a> +</span><span id="preprocess-159"><a href="#preprocess-159"><span class="linenos">159</span></a> <span class="k">return</span> <span class="n">_to_sql</span> </span></pre></div> @@ -462,16 +558,16 @@ expression to SQL, using an appropriate <code>Generator.TRANSFORMS</code> functi </div> <a class="headerlink" href="#delegate"></a> - <div class="pdoc-code codehilite"><pre><span></span><span id="delegate-129"><a href="#delegate-129"><span class="linenos">129</span></a><span class="k">def</span> <span class="nf">delegate</span><span class="p">(</span><span class="n">attr</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">:</span> -</span><span id="delegate-130"><a href="#delegate-130"><span class="linenos">130</span></a><span class="w"> </span><span class="sd">"""</span> -</span><span id="delegate-131"><a href="#delegate-131"><span class="linenos">131</span></a><span class="sd"> Create a new method that delegates to `attr`. This is useful for creating `Generator.TRANSFORMS`</span> -</span><span id="delegate-132"><a href="#delegate-132"><span class="linenos">132</span></a><span class="sd"> functions that delegate to existing generator methods.</span> -</span><span id="delegate-133"><a href="#delegate-133"><span class="linenos">133</span></a><span class="sd"> """</span> -</span><span id="delegate-134"><a href="#delegate-134"><span class="linenos">134</span></a> -</span><span id="delegate-135"><a href="#delegate-135"><span class="linenos">135</span></a> <span class="k">def</span> <span class="nf">_transform</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> -</span><span id="delegate-136"><a href="#delegate-136"><span class="linenos">136</span></a> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr</span><span class="p">)(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> -</span><span id="delegate-137"><a href="#delegate-137"><span class="linenos">137</span></a> -</span><span id="delegate-138"><a href="#delegate-138"><span class="linenos">138</span></a> <span class="k">return</span> <span class="n">_transform</span> + <div class="pdoc-code codehilite"><pre><span></span><span id="delegate-162"><a href="#delegate-162"><span class="linenos">162</span></a><span class="k">def</span> <span class="nf">delegate</span><span class="p">(</span><span class="n">attr</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-></span> <span class="n">t</span><span class="o">.</span><span class="n">Callable</span><span class="p">:</span> +</span><span id="delegate-163"><a href="#delegate-163"><span class="linenos">163</span></a><span class="w"> </span><span class="sd">"""</span> +</span><span id="delegate-164"><a href="#delegate-164"><span class="linenos">164</span></a><span class="sd"> Create a new method that delegates to `attr`. This is useful for creating `Generator.TRANSFORMS`</span> +</span><span id="delegate-165"><a href="#delegate-165"><span class="linenos">165</span></a><span class="sd"> functions that delegate to existing generator methods.</span> +</span><span id="delegate-166"><a href="#delegate-166"><span class="linenos">166</span></a><span class="sd"> """</span> +</span><span id="delegate-167"><a href="#delegate-167"><span class="linenos">167</span></a> +</span><span id="delegate-168"><a href="#delegate-168"><span class="linenos">168</span></a> <span class="k">def</span> <span class="nf">_transform</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> +</span><span id="delegate-169"><a href="#delegate-169"><span class="linenos">169</span></a> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr</span><span class="p">)(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> +</span><span id="delegate-170"><a href="#delegate-170"><span class="linenos">170</span></a> +</span><span id="delegate-171"><a href="#delegate-171"><span class="linenos">171</span></a> <span class="k">return</span> <span class="n">_transform</span> </span></pre></div> |