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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>2.9. Deletions</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="tutorial-update.html" title="2.8. Updates" /><link rel="next" href="tutorial-advanced.html" title="Chapter 3. Advanced Features" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">2.9. Deletions</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-update.html" title="2.8. Updates">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><th width="60%" align="center">Chapter 2. The <acronym class="acronym">SQL</acronym> Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.7 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-advanced.html" title="Chapter 3. Advanced Features">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-DELETE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">2.9. Deletions</h2></div></div></div><a id="id-1.4.4.10.2" class="indexterm"></a><p>
Rows can be removed from a table using the <code class="command">DELETE</code>
command.
Suppose you are no longer interested in the weather of Hayward.
Then you can do the following to delete those rows from the table:
</p><pre class="programlisting">
DELETE FROM weather WHERE city = 'Hayward';
</pre><p>
All weather records belonging to Hayward are removed.
</p><pre class="programlisting">
SELECT * FROM weather;
</pre><p>
</p><pre class="screen">
city | temp_lo | temp_hi | prcp | date
---------------+---------+---------+------+------------
San Francisco | 46 | 50 | 0.25 | 1994-11-27
San Francisco | 41 | 55 | 0 | 1994-11-29
(2 rows)
</pre><p>
</p><p>
One should be wary of statements of the form
</p><pre class="synopsis">
DELETE FROM <em class="replaceable"><code>tablename</code></em>;
</pre><p>
Without a qualification, <code class="command">DELETE</code> will
remove <span class="emphasis"><em>all</em></span> rows from the given table, leaving it
empty. The system will not request confirmation before
doing this!
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