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<?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>VALUES</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="sql-vacuum.html" title="VACUUM" /><link rel="next" href="reference-client.html" title="PostgreSQL Client Applications" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">VALUES</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-vacuum.html" title="VACUUM">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="reference-client.html" title="PostgreSQL Client Applications">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-VALUES"><div class="titlepage"></div><a id="id-1.9.3.185.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">VALUES</span></h2><p>VALUES — compute a set of rows</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
VALUES ( <em class="replaceable"><code>expression</code></em> [, ...] ) [, ...]
[ ORDER BY <em class="replaceable"><code>sort_expression</code></em> [ ASC | DESC | USING <em class="replaceable"><code>operator</code></em> ] [, ...] ]
[ LIMIT { <em class="replaceable"><code>count</code></em> | ALL } ]
[ OFFSET <em class="replaceable"><code>start</code></em> [ ROW | ROWS ] ]
[ FETCH { FIRST | NEXT } [ <em class="replaceable"><code>count</code></em> ] { ROW | ROWS } ONLY ]
</pre></div><div class="refsect1" id="id-1.9.3.185.5"><h2>Description</h2><p>
<code class="command">VALUES</code> computes a row value or set of row values
specified by value expressions. It is most commonly used to generate
a <span class="quote">“<span class="quote">constant table</span>”</span> within a larger command, but it can be
used on its own.
</p><p>
When more than one row is specified, all the rows must have the same
number of elements. The data types of the resulting table's columns are
determined by combining the explicit or inferred types of the expressions
appearing in that column, using the same rules as for <code class="literal">UNION</code>
(see <a class="xref" href="typeconv-union-case.html" title="10.5. UNION, CASE, and Related Constructs">Section 10.5</a>).
</p><p>
Within larger commands, <code class="command">VALUES</code> is syntactically allowed
anywhere that <code class="command">SELECT</code> is. Because it is treated like a
<code class="command">SELECT</code> by the grammar, it is possible to use
the <code class="literal">ORDER BY</code>, <code class="literal">LIMIT</code> (or
equivalently <code class="literal">FETCH FIRST</code>),
and <code class="literal">OFFSET</code> clauses with a
<code class="command">VALUES</code> command.
</p></div><div class="refsect1" id="id-1.9.3.185.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>expression</code></em></span></dt><dd><p>
A constant or expression to compute and insert at the indicated place
in the resulting table (set of rows). In a <code class="command">VALUES</code> list
appearing at the top level of an <code class="command">INSERT</code>, an
<em class="replaceable"><code>expression</code></em> can be replaced
by <code class="literal">DEFAULT</code> to indicate that the destination column's
default value should be inserted. <code class="literal">DEFAULT</code> cannot
be used when <code class="command">VALUES</code> appears in other contexts.
</p></dd><dt><span class="term"><em class="replaceable"><code>sort_expression</code></em></span></dt><dd><p>
An expression or integer constant indicating how to sort the result
rows. This expression can refer to the columns of the
<code class="command">VALUES</code> result as <code class="literal">column1</code>, <code class="literal">column2</code>,
etc. For more details see
<a class="xref" href="sql-select.html#SQL-ORDERBY" title="ORDER BY Clause">ORDER BY Clause</a>
in the <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a> documentation.
</p></dd><dt><span class="term"><em class="replaceable"><code>operator</code></em></span></dt><dd><p>
A sorting operator. For details see
<a class="xref" href="sql-select.html#SQL-ORDERBY" title="ORDER BY Clause">ORDER BY Clause</a>
in the <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a> documentation.
</p></dd><dt><span class="term"><em class="replaceable"><code>count</code></em></span></dt><dd><p>
The maximum number of rows to return. For details see
<a class="xref" href="sql-select.html#SQL-LIMIT" title="LIMIT Clause">LIMIT Clause</a>
in the <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a> documentation.
</p></dd><dt><span class="term"><em class="replaceable"><code>start</code></em></span></dt><dd><p>
The number of rows to skip before starting to return rows.
For details see <a class="xref" href="sql-select.html#SQL-LIMIT" title="LIMIT Clause">LIMIT Clause</a>
in the <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a> documentation.
</p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.185.7"><h2>Notes</h2><p>
<code class="command">VALUES</code> lists with very large numbers of rows should be avoided,
as you might encounter out-of-memory failures or poor performance.
<code class="command">VALUES</code> appearing within <code class="command">INSERT</code> is a special case
(because the desired column types are known from the <code class="command">INSERT</code>'s
target table, and need not be inferred by scanning the <code class="command">VALUES</code>
list), so it can handle larger lists than are practical in other contexts.
</p></div><div class="refsect1" id="id-1.9.3.185.8"><h2>Examples</h2><p>
A bare <code class="command">VALUES</code> command:
</p><pre class="programlisting">
VALUES (1, 'one'), (2, 'two'), (3, 'three');
</pre><p>
This will return a table of two columns and three rows. It's effectively
equivalent to:
</p><pre class="programlisting">
SELECT 1 AS column1, 'one' AS column2
UNION ALL
SELECT 2, 'two'
UNION ALL
SELECT 3, 'three';
</pre><p>
</p><p>
More usually, <code class="command">VALUES</code> is used within a larger SQL command.
The most common use is in <code class="command">INSERT</code>:
</p><pre class="programlisting">
INSERT INTO films (code, title, did, date_prod, kind)
VALUES ('T_601', 'Yojimbo', 106, '1961-06-16', 'Drama');
</pre><p>
</p><p>
In the context of <code class="command">INSERT</code>, entries of a <code class="command">VALUES</code> list
can be <code class="literal">DEFAULT</code> to indicate that the column default
should be used here instead of specifying a value:
</p><pre class="programlisting">
INSERT INTO films VALUES
('UA502', 'Bananas', 105, DEFAULT, 'Comedy', '82 minutes'),
('T_601', 'Yojimbo', 106, DEFAULT, 'Drama', DEFAULT);
</pre><p>
</p><p>
<code class="command">VALUES</code> can also be used where a sub-<code class="command">SELECT</code> might
be written, for example in a <code class="literal">FROM</code> clause:
</p><pre class="programlisting">
SELECT f.*
FROM films f, (VALUES('MGM', 'Horror'), ('UA', 'Sci-Fi')) AS t (studio, kind)
WHERE f.studio = t.studio AND f.kind = t.kind;
UPDATE employees SET salary = salary * v.increase
FROM (VALUES(1, 200000, 1.2), (2, 400000, 1.4)) AS v (depno, target, increase)
WHERE employees.depno = v.depno AND employees.sales >= v.target;
</pre><p>
Note that an <code class="literal">AS</code> clause is required when <code class="command">VALUES</code>
is used in a <code class="literal">FROM</code> clause, just as is true for
<code class="command">SELECT</code>. It is not required that the <code class="literal">AS</code> clause
specify names for all the columns, but it's good practice to do so.
(The default column names for <code class="command">VALUES</code> are <code class="literal">column1</code>,
<code class="literal">column2</code>, etc. in <span class="productname">PostgreSQL</span>, but
these names might be different in other database systems.)
</p><p>
When <code class="command">VALUES</code> is used in <code class="command">INSERT</code>, the values are all
automatically coerced to the data type of the corresponding destination
column. When it's used in other contexts, it might be necessary to specify
the correct data type. If the entries are all quoted literal constants,
coercing the first is sufficient to determine the assumed type for all:
</p><pre class="programlisting">
SELECT * FROM machines
WHERE ip_address IN (VALUES('192.168.0.1'::inet), ('192.168.0.10'), ('192.168.1.43'));
</pre><div class="tip"><h3 class="title">Tip</h3><p>
For simple <code class="literal">IN</code> tests, it's better to rely on the
<a class="link" href="functions-comparisons.html#FUNCTIONS-COMPARISONS-IN-SCALAR" title="9.24.1. IN">list-of-scalars</a>
form of <code class="literal">IN</code> than to write a <code class="command">VALUES</code>
query as shown above. The list of scalars method requires less writing
and is often more efficient.
</p></div></div><div class="refsect1" id="id-1.9.3.185.9"><h2>Compatibility</h2><p><code class="command">VALUES</code> conforms to the SQL standard.
<code class="literal">LIMIT</code> and <code class="literal">OFFSET</code> are
<span class="productname">PostgreSQL</span> extensions; see also
under <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a>.
</p></div><div class="refsect1" id="id-1.9.3.185.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-insert.html" title="INSERT"><span class="refentrytitle">INSERT</span></a>, <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-vacuum.html" title="VACUUM">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="reference-client.html" title="PostgreSQL Client Applications">Next</a></td></tr><tr><td width="40%" align="left" valign="top">VACUUM </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> PostgreSQL Client Applications</td></tr></table></div></body></html>
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