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1<?xml version="1.0" encoding="UTF-8" standalone="no"?>2<!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>7.7. VALUES Lists</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="queries-limit.html" title="7.6. LIMIT and OFFSET" /><link rel="next" href="queries-with.html" title="7.8. WITH Queries (Common Table Expressions)" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">7.7. <code class="literal">VALUES</code> Lists</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="queries-limit.html" title="7.6. LIMIT and OFFSET">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="queries.html" title="Chapter 7. Queries">Up</a></td><th width="60%" align="center">Chapter 7. Queries</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="queries-with.html" title="7.8. WITH Queries (Common Table Expressions)">Next</a></td></tr></table><hr /></div><div class="sect1" id="QUERIES-VALUES"><div class="titlepage"><div><div><h2 class="title" style="clear: both">7.7. <code class="literal">VALUES</code> Lists <a href="#QUERIES-VALUES" class="id_link">#</a></h2></div></div></div><a id="id-1.5.6.11.2" class="indexterm"></a><p>3   <code class="literal">VALUES</code> provides a way to generate a <span class="quote">“<span class="quote">constant table</span>”</span>4   that can be used in a query without having to actually create and populate5   a table on-disk.  The syntax is6</p><pre class="synopsis">7VALUES ( <em class="replaceable"><code>expression</code></em> [, ...] ) [, ...]8</pre><p>9   Each parenthesized list of expressions generates a row in the table.10   The lists must all have the same number of elements (i.e., the number11   of columns in the table), and corresponding entries in each list must12   have compatible data types.  The actual data type assigned to each column13   of the result is determined using the same rules as for <code class="literal">UNION</code>14   (see <a class="xref" href="typeconv-union-case.html" title="10.5. UNION, CASE, and Related Constructs">Section 10.5</a>).15  </p><p>16   As an example:17</p><pre class="programlisting">18VALUES (1, 'one'), (2, 'two'), (3, 'three');19</pre><p>20 21   will return a table of two columns and three rows.  It's effectively22   equivalent to:23</p><pre class="programlisting">24SELECT 1 AS column1, 'one' AS column225UNION ALL26SELECT 2, 'two'27UNION ALL28SELECT 3, 'three';29</pre><p>30 31   By default, <span class="productname">PostgreSQL</span> assigns the names32   <code class="literal">column1</code>, <code class="literal">column2</code>, etc. to the columns of a33   <code class="literal">VALUES</code> table.  The column names are not specified by the34   SQL standard and different database systems do it differently, so35   it's usually better to override the default names with a table alias36   list, like this:37</p><pre class="programlisting">38=&gt; SELECT * FROM (VALUES (1, 'one'), (2, 'two'), (3, 'three')) AS t (num,letter);39 num | letter40-----+--------41   1 | one42   2 | two43   3 | three44(3 rows)45</pre><p>46  </p><p>47   Syntactically, <code class="literal">VALUES</code> followed by expression lists is48   treated as equivalent to:49</p><pre class="synopsis">50SELECT <em class="replaceable"><code>select_list</code></em> FROM <em class="replaceable"><code>table_expression</code></em>51</pre><p>52   and can appear anywhere a <code class="literal">SELECT</code> can.  For example, you can53   use it as part of a <code class="literal">UNION</code>, or attach a54   <em class="replaceable"><code>sort_specification</code></em> (<code class="literal">ORDER BY</code>,55   <code class="literal">LIMIT</code>, and/or <code class="literal">OFFSET</code>) to it.  <code class="literal">VALUES</code>56   is most commonly used as the data source in an <code class="command">INSERT</code> command,57   and next most commonly as a subquery.58  </p><p>59   For more information see <a class="xref" href="sql-values.html" title="VALUES"><span class="refentrytitle">VALUES</span></a>.60  </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="queries-limit.html" title="7.6. LIMIT and OFFSET">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="queries.html" title="Chapter 7. Queries">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="queries-with.html" title="7.8. WITH Queries (Common Table Expressions)">Next</a></td></tr><tr><td width="40%" align="left" valign="top">7.6. <code class="literal">LIMIT</code> and <code class="literal">OFFSET</code> </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"> 7.8. <code class="literal">WITH</code> Queries (Common Table Expressions)</td></tr></table></div></body></html>