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<!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>6.4. Returning Data from Modified Rows</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="dml-delete.html" title="6.3. Deleting Data" /><link rel="next" href="queries.html" title="Chapter 7. Queries" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">6.4. Returning Data from Modified Rows</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="dml-delete.html" title="6.3. Deleting Data">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="dml.html" title="Chapter 6. Data Manipulation">Up</a></td><th width="60%" align="center">Chapter 6. Data Manipulation</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.html" title="Chapter 7. Queries">Next</a></td></tr></table><hr /></div><div class="sect1" id="DML-RETURNING"><div class="titlepage"><div><div><h2 class="title" style="clear: both">6.4. Returning Data from Modified Rows <a href="#DML-RETURNING" class="id_link">#</a></h2></div></div></div><a id="id-1.5.5.6.2" class="indexterm"></a><a id="id-1.5.5.6.3" class="indexterm"></a><a id="id-1.5.5.6.4" class="indexterm"></a><a id="id-1.5.5.6.5" class="indexterm"></a><p>
   Sometimes it is useful to obtain data from modified rows while they are
   being manipulated.  The <code class="command">INSERT</code>, <code class="command">UPDATE</code>,
   and <code class="command">DELETE</code> commands all have an
   optional <code class="literal">RETURNING</code> clause that supports this.  Use
   of <code class="literal">RETURNING</code> avoids performing an extra database query to
   collect the data, and is especially valuable when it would otherwise be
   difficult to identify the modified rows reliably.
  </p><p>
   The allowed contents of a <code class="literal">RETURNING</code> clause are the same as
   a <code class="command">SELECT</code> command's output list
   (see <a class="xref" href="queries-select-lists.html" title="7.3. Select Lists">Section 7.3</a>).  It can contain column
   names of the command's target table, or value expressions using those
   columns.  A common shorthand is <code class="literal">RETURNING *</code>, which selects
   all columns of the target table in order.
  </p><p>
   In an <code class="command">INSERT</code>, the data available to <code class="literal">RETURNING</code> is
   the row as it was inserted.  This is not so useful in trivial inserts,
   since it would just repeat the data provided by the client.  But it can
   be very handy when relying on computed default values.  For example,
   when using a <a class="link" href="datatype-numeric.html#DATATYPE-SERIAL" title="8.1.4. Serial Types"><code class="type">serial</code></a>
   column to provide unique identifiers, <code class="literal">RETURNING</code> can return
   the ID assigned to a new row:
</p><pre class="programlisting">
CREATE TABLE users (firstname text, lastname text, id serial primary key);

INSERT INTO users (firstname, lastname) VALUES ('Joe', 'Cool') RETURNING id;
</pre><p>
   The <code class="literal">RETURNING</code> clause is also very useful
   with <code class="literal">INSERT ... SELECT</code>.
  </p><p>
   In an <code class="command">UPDATE</code>, the data available to <code class="literal">RETURNING</code> is
   the new content of the modified row.  For example:
</p><pre class="programlisting">
UPDATE products SET price = price * 1.10
  WHERE price &lt;= 99.99
  RETURNING name, price AS new_price;
</pre><p>
  </p><p>
   In a <code class="command">DELETE</code>, the data available to <code class="literal">RETURNING</code> is
   the content of the deleted row.  For example:
</p><pre class="programlisting">
DELETE FROM products
  WHERE obsoletion_date = 'today'
  RETURNING *;
</pre><p>
  </p><p>
   If there are triggers (<a class="xref" href="triggers.html" title="Chapter 39. Triggers">Chapter 39</a>) on the target table,
   the data available to <code class="literal">RETURNING</code> is the row as modified by
   the triggers.  Thus, inspecting columns computed by triggers is another
   common use-case for <code class="literal">RETURNING</code>.
  </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="dml-delete.html" title="6.3. Deleting Data">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="dml.html" title="Chapter 6. Data Manipulation">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="queries.html" title="Chapter 7. Queries">Next</a></td></tr><tr><td width="40%" align="left" valign="top">6.3. Deleting Data </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"> Chapter 7. Queries</td></tr></table></div></body></html>