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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>6.3. Deleting Data</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-update.html" title="6.2. Updating Data" /><link rel="next" href="dml-returning.html" title="6.4. Returning Data from Modified Rows" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">6.3. Deleting Data</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="dml-update.html" title="6.2. Updating 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="dml-returning.html" title="6.4. Returning Data from Modified Rows">Next</a></td></tr></table><hr /></div><div class="sect1" id="DML-DELETE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">6.3. Deleting Data <a href="#DML-DELETE" class="id_link">#</a></h2></div></div></div><a id="id-1.5.5.5.2" class="indexterm"></a><a id="id-1.5.5.5.3" class="indexterm"></a><p>3   So far we have explained how to add data to tables and how to4   change data.  What remains is to discuss how to remove data that is5   no longer needed.  Just as adding data is only possible in whole6   rows, you can only remove entire rows from a table.  In the7   previous section we explained that SQL does not provide a way to8   directly address individual rows.  Therefore, removing rows can9   only be done by specifying conditions that the rows to be removed10   have to match.  If you have a primary key in the table then you can11   specify the exact row.  But you can also remove groups of rows12   matching a condition, or you can remove all rows in the table at13   once.14  </p><p>15   You use the <a class="xref" href="sql-delete.html" title="DELETE"><span class="refentrytitle">DELETE</span></a>16   command to remove rows; the syntax is very similar to the17   <a class="xref" href="sql-update.html" title="UPDATE"><span class="refentrytitle">UPDATE</span></a> command.  For instance, to remove all18   rows from the products table that have a price of 10, use:19</p><pre class="programlisting">20DELETE FROM products WHERE price = 10;21</pre><p>22  </p><p>23   If you simply write:24</p><pre class="programlisting">25DELETE FROM products;26</pre><p>27   then all rows in the table will be deleted!  Caveat programmer.28  </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="dml-update.html" title="6.2. Updating 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="dml-returning.html" title="6.4. Returning Data from Modified Rows">Next</a></td></tr><tr><td width="40%" align="left" valign="top">6.2. Updating 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"> 6.4. Returning Data from Modified Rows</td></tr></table></div></body></html>