<!--
doc/src/sgml/ref/alter_sequence.sgml
PostgreSQL documentation
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<refentry id="sql-altersequence">
 <indexterm zone="sql-altersequence">
  <primary>ALTER SEQUENCE</primary>
 </indexterm>

 <refmeta>
  <refentrytitle>ALTER SEQUENCE</refentrytitle>
  <manvolnum>7</manvolnum>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>ALTER SEQUENCE</refname>
  <refpurpose>
   change the definition of a sequence generator
  </refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
    [ AS <replaceable class="parameter">data_type</replaceable> ]
    [ INCREMENT [ BY ] <replaceable class="parameter">increment</replaceable> ]
    [ MINVALUE <replaceable class="parameter">minvalue</replaceable> | NO MINVALUE ] [ MAXVALUE <replaceable class="parameter">maxvalue</replaceable> | NO MAXVALUE ]
    [ [ NO ] CYCLE ]
    [ START [ WITH ] <replaceable class="parameter">start</replaceable> ]
    [ RESTART [ [ WITH ] <replaceable class="parameter">restart</replaceable> ] ]
    [ CACHE <replaceable class="parameter">cache</replaceable> ]
    [ OWNED BY { <replaceable class="parameter">table_name</replaceable>.<replaceable class="parameter">column_name</replaceable> | NONE } ]
ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> SET { LOGGED | UNLOGGED }
ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> OWNER TO { <replaceable class="parameter">new_owner</replaceable> | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
ALTER SEQUENCE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>ALTER SEQUENCE</command> changes the parameters of an existing
   sequence generator.  Any parameters not specifically set in the
   <command>ALTER SEQUENCE</command> command retain their prior settings.
  </para>

  <para>
   You must own the sequence to use <command>ALTER SEQUENCE</command>.
   To change a sequence's schema, you must also have <literal>CREATE</literal>
   privilege on the new schema.
   To alter the owner, you must be able to <literal>SET ROLE</literal> to the
   new owning role, and that role must have <literal>CREATE</literal>
   privilege on the sequence's schema.
   (These restrictions enforce that altering the owner
   doesn't do anything you couldn't do by dropping and recreating the sequence.
   However, a superuser can alter ownership of any sequence anyway.)
  </para>
 </refsect1>

 <refsect1>
  <title>Parameters</title>

   <para>
    <variablelist>
     <varlistentry>
      <term><replaceable class="parameter">name</replaceable></term>
      <listitem>
       <para>
        The name (optionally schema-qualified) of a sequence to be altered.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><literal>IF EXISTS</literal></term>
      <listitem>
       <para>
        Do not throw an error if the sequence does not exist. A notice is issued
        in this case.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="parameter">data_type</replaceable></term>
      <listitem>
       <para>
        The optional
        clause <literal>AS <replaceable class="parameter">data_type</replaceable></literal>
        changes the data type of the sequence.  Valid types are
        <literal>smallint</literal>, <literal>integer</literal>,
        and <literal>bigint</literal>.
       </para>

       <para>
        Changing the data type automatically changes the minimum and maximum
        values of the sequence if and only if the previous minimum and maximum
        values were the minimum