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Green_GoodERP18_FSJ_Standard/PostgreSQL/doc/postgresql/html/sql-dropaggregate.html

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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>DROP AGGREGATE</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 V1.79.1" /><link rel="prev" href="sql-drop-access-method.html" title="DROP ACCESS METHOD" /><link rel="next" href="sql-dropcast.html" title="DROP CAST" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">DROP AGGREGATE</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-drop-access-method.html" title="DROP ACCESS METHOD">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 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-dropcast.html" title="DROP CAST">Next</a></td></tr></table><hr></hr></div><div class="refentry" id="SQL-DROPAGGREGATE"><div class="titlepage"></div><a id="id-1.9.3.104.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">DROP AGGREGATE</span></h2><p>DROP AGGREGATE — remove an aggregate function</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">

  3. DROP AGGREGATE [ IF EXISTS ] <em class="replaceable"><code>name</code></em> ( <em class="replaceable"><code>aggregate_signature</code></em> ) [, ...] [ CASCADE | RESTRICT ]

  4. 

  5. <span class="phrase">where <em class="replaceable"><code>aggregate_signature</code></em> is:</span>

  6. 

  7. * |

  8. [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ] |

  9. [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ] ] ORDER BY [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [ , ... ]

  10. </pre></div><div class="refsect1" id="id-1.9.3.104.5"><h2>Description</h2><p>

  11.    <code class="command">DROP AGGREGATE</code> removes an existing

  12.    aggregate function. To execute this command the current

  13.    user must be the owner of the aggregate function.

  14.   </p></div><div class="refsect1" id="id-1.9.3.104.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">IF EXISTS</code></span></dt><dd><p>

  15.       Do not throw an error if the aggregate does not exist. A notice is issued

  16.       in this case.

  17.      </p></dd><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p>

  18.       The name (optionally schema-qualified) of an existing aggregate function.

  19.      </p></dd><dt><span class="term"><em class="replaceable"><code>argmode</code></em></span></dt><dd><p>

  20.       The mode of an argument: <code class="literal">IN</code> or <code class="literal">VARIADIC</code>.

  21.       If omitted, the default is <code class="literal">IN</code>.

  22.      </p></dd><dt><span class="term"><em class="replaceable"><code>argname</code></em></span></dt><dd><p>

  23.       The name of an argument.

  24.       Note that <code class="command">DROP AGGREGATE</code> does not actually pay

  25.       any attention to argument names, since only the argument data

  26.       types are needed to determine the aggregate function's identity.

  27.      </p></dd><dt><span class="term"><em class="replaceable"><code>argtype</code></em></span></dt><dd><p>

  28.       An input data type on which the aggregate function operates.

  29.       To reference a zero-argument aggregate function, write <code class="literal">*</code>

  30.       in place of the list of argument specifications.

  31.       To reference an ordered-set aggregate function, write

  32.       <code class="literal">ORDER BY</code> between the direct and aggregated argument

  33.       specifications.

  34.      </p></dd><dt><span class="term"><code class="literal">CASCADE</code></span></dt><dd><p>

  35.       Automatically drop objects that depend on the aggregate function

  36.       (such as views using it),

  37.       and in turn all objects that depend on those objects

  38.       (see <a class="xref" href="ddl-depend.html" title="5.14. Dependency Tracking">Section 5.14</a>).

  39.      </p></dd><dt><span class="term"><code class="literal">RESTRICT</code></span></dt><dd><p>

  40.       Refuse to drop the aggregate function if any objects depend on

  41.       it.  This is the default.

  42.      </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.104.7"><h2>Notes</h2><p>

  43.     Alternative syntaxes for referencing ordered-set aggregates

  44.     are described under <a class="xref" href="sql-alteraggregate.html" title="ALTER AGGREGATE"><span class="refentrytitle">ALTER AGGREGATE</span></a>.

  45.    </p></div><div class="refsect1" id="id-1.9.3.104.8"><h2>Examples</h2><p>

  46.    To remove the aggregate function <code class="literal">myavg</code> for type

  47.    <code class="type">integer</code>:

  48. </p><pre class="programlisting">

  49. DROP AGGREGATE myavg(integer);

  50. </pre><p>

  51.   </p><p>

  52.    To remove the hypothetical-set aggregate function <code class="literal">myrank</code>,

  53.    which takes an arbitrary list of ordering columns and a matching list

  54.    of direct arguments:

  55. </p><pre class="programlisting">

  56. DROP AGGREGATE myrank(VARIADIC "any" ORDER BY VARIADIC "any");

  57. </pre><p>

  58.   </p><p>

  59.    To remove multiple aggregate functions in one command:

  60. </p><pre class="programlisting">

  61. DROP AGGREGATE myavg(integer), myavg(bigint);

  62. </pre></div><div class="refsect1" id="id-1.9.3.104.9"><h2>Compatibility</h2><p>

  63.    There is no <code class="command">DROP AGGREGATE</code> statement in the SQL

  64.    standard.

  65.   </p></div><div class="refsect1" id="id-1.9.3.104.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-alteraggregate.html" title="ALTER AGGREGATE"><span class="refentrytitle">ALTER AGGREGATE</span></a>, <a class="xref" href="sql-createaggregate.html" title="CREATE AGGREGATE"><span class="refentrytitle">CREATE AGGREGATE</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-drop-access-method.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-dropcast.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">DROP ACCESS METHOD </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> DROP CAST</td></tr></table></div></body></html>
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