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diff --git a/doc/src/sgml/html/plpython-util.html b/doc/src/sgml/html/plpython-util.html new file mode 100644 index 0000000..63eeac3 --- /dev/null +++ b/doc/src/sgml/html/plpython-util.html @@ -0,0 +1,60 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>46.9. Utility Functions</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="plpython-transactions.html" title="46.8. Transaction Management" /><link rel="next" href="plpython-python23.html" title="46.10. Python 2 vs. Python 3" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">46.9. Utility Functions</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="plpython-transactions.html" title="46.8. Transaction Management">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="plpython.html" title="Chapter 46. PL/Python — Python Procedural Language">Up</a></td><th width="60%" align="center">Chapter 46. PL/Python — Python Procedural Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="plpython-python23.html" title="46.10. Python 2 vs. Python 3">Next</a></td></tr></table><hr /></div><div class="sect1" id="PLPYTHON-UTIL"><div class="titlepage"><div><div><h2 class="title" style="clear: both">46.9. Utility Functions</h2></div></div></div><p> + The <code class="literal">plpy</code> module also provides the functions + </p><table border="0" summary="Simple list" class="simplelist"><tr><td><code class="literal">plpy.debug(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.log(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.info(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.notice(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.warning(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.error(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr><tr><td><code class="literal">plpy.fatal(<em class="replaceable"><code>msg, **kwargs</code></em>)</code></td></tr></table><p> + <a id="id-1.8.11.17.2.3" class="indexterm"></a> + <code class="function">plpy.error</code> and <code class="function">plpy.fatal</code> + actually raise a Python exception which, if uncaught, propagates out to + the calling query, causing the current transaction or subtransaction to + be aborted. <code class="literal">raise plpy.Error(<em class="replaceable"><code>msg</code></em>)</code> and + <code class="literal">raise plpy.Fatal(<em class="replaceable"><code>msg</code></em>)</code> are + equivalent to calling <code class="literal">plpy.error(<em class="replaceable"><code>msg</code></em>)</code> and + <code class="literal">plpy.fatal(<em class="replaceable"><code>msg</code></em>)</code>, respectively but + the <code class="literal">raise</code> form does not allow passing keyword arguments. + The other functions only generate messages of different priority levels. + Whether messages of a particular priority are reported to the client, + written to the server log, or both is controlled by the + <a class="xref" href="runtime-config-logging.html#GUC-LOG-MIN-MESSAGES">log_min_messages</a> and + <a class="xref" href="runtime-config-client.html#GUC-CLIENT-MIN-MESSAGES">client_min_messages</a> configuration + variables. See <a class="xref" href="runtime-config.html" title="Chapter 20. Server Configuration">Chapter 20</a> for more information. + </p><p> + The <em class="replaceable"><code>msg</code></em> argument is given as a positional argument. For + backward compatibility, more than one positional argument can be given. In + that case, the string representation of the tuple of positional arguments + becomes the message reported to the client. + </p><p> + The following keyword-only arguments are accepted: + </p><table border="0" summary="Simple list" class="simplelist"><tr><td><code class="literal">detail</code></td></tr><tr><td><code class="literal">hint</code></td></tr><tr><td><code class="literal">sqlstate</code></td></tr><tr><td><code class="literal">schema_name</code></td></tr><tr><td><code class="literal">table_name</code></td></tr><tr><td><code class="literal">column_name</code></td></tr><tr><td><code class="literal">datatype_name</code></td></tr><tr><td><code class="literal">constraint_name</code></td></tr></table><p> + The string representation of the objects passed as keyword-only arguments + is used to enrich the messages reported to the client. For example: + +</p><pre class="programlisting"> +CREATE FUNCTION raise_custom_exception() RETURNS void AS $$ +plpy.error("custom exception message", + detail="some info about exception", + hint="hint for users") +$$ LANGUAGE plpython3u; + +=# SELECT raise_custom_exception(); +ERROR: plpy.Error: custom exception message +DETAIL: some info about exception +HINT: hint for users +CONTEXT: Traceback (most recent call last): + PL/Python function "raise_custom_exception", line 4, in <module> + hint="hint for users") +PL/Python function "raise_custom_exception" +</pre><p> + </p><p> + Another set of utility functions are + <code class="literal">plpy.quote_literal(<em class="replaceable"><code>string</code></em>)</code>, + <code class="literal">plpy.quote_nullable(<em class="replaceable"><code>string</code></em>)</code>, and + <code class="literal">plpy.quote_ident(<em class="replaceable"><code>string</code></em>)</code>. They + are equivalent to the built-in quoting functions described in <a class="xref" href="functions-string.html" title="9.4. String Functions and Operators">Section 9.4</a>. They are useful when constructing + ad-hoc queries. A PL/Python equivalent of dynamic SQL from <a class="xref" href="plpgsql-statements.html#PLPGSQL-QUOTE-LITERAL-EXAMPLE" title="Example 43.1. Quoting Values in Dynamic Queries">Example 43.1</a> would be: +</p><pre class="programlisting"> +plpy.execute("UPDATE tbl SET %s = %s WHERE key = %s" % ( + plpy.quote_ident(colname), + plpy.quote_nullable(newvalue), + plpy.quote_literal(keyvalue))) +</pre><p> + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="plpython-transactions.html" title="46.8. Transaction Management">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="plpython.html" title="Chapter 46. 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