<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_user.sgml,v 1.9 1999/11/30 03:57:22 momjian Exp $
Postgres documentation
-->

<refentry id="SQL-ALTERUSER">
 <refmeta>
  <refentrytitle id="sql-alteruser-title">
   ALTER USER
  </refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>
 <refnamediv>
  <refname>
   ALTER USER
  </refname>
  <refpurpose>
   Modifies user account information
  </refpurpose>
 </refnamediv>
 <refsynopsisdiv>
  <refsynopsisdivinfo>
   <date>1999-07-20</date>
  </refsynopsisdivinfo>
  <synopsis>
ALTER USER <replaceable class="PARAMETER">username</replaceable>
    [ WITH
     [ SYSID <replaceable class="PARAMETER">uid</replaceable> ]
     [ PASSWORD <replaceable class="PARAMETER">password</replaceable> ] ]
    [ CREATEDB | NOCREATEDB ] [ CREATEUSER | NOCREATEUSER ]
    [ IN GROUP <replaceable class="PARAMETER">groupname</replaceable> [, ...] ]
    [ VALID UNTIL '<replaceable class="PARAMETER">abstime</replaceable>' ]
  </synopsis>

  <refsect2 id="R2-SQL-ALTERUSER-1">
   <refsect2info>
    <date>1998-09-08</date>
   </refsect2info>
   <title>
    Inputs
   </title>

   <para>
    Refer to <command>CREATE USER</command> for a detailed description of each
    clause.
   </para>

   <para>
    <variablelist>
     <varlistentry>
      <term><replaceable class="PARAMETER"> username </replaceable></term>
      <listitem>
       <para>
	The Postgres account name of the user whose details are to be altered.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="PARAMETER"> password </replaceable></term>
      <listitem>
       <para>
	The new password to be used for this account.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="parameter">uid</replaceable></term>
      <listitem>
       <para>
        The new <productname>PostgreSQL</productname> user id of the user.
        Since this number is used as a key into the
        <literal>pg_shadow</literal>/<literal>pg_user</literal> table
        throughout the system catalogs, it is not recommended that you change
        it unless the user in question does not own anything at all and/or
        you really know what you are doing. Note that it is not necessary that
        database and <acronym>UNIX</acronym> user ids match, but some people
        choose to keep the numbers the same.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="PARAMETER"> groupname </replaceable></term>
      <listitem>
       <para>
	The name of an access group into which this account is to be put.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="PARAMETER"> abstime </replaceable></term>
      <listitem>
       <para>
	The date (and, optionally, the time)
	at which this user's access is to be terminated.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
   </para>
  </refsect2>
    
  <refsect2 id="R2-SQL-ALTERUSER-2">
   <refsect2info>
    <date>1998-09-08</date>
   </refsect2info>
   <title>
    Outputs
   </title>
   <para>
    <variablelist>
     <varlistentry>
      <term><computeroutput>
ALTER USER
       </computeroutput></term>
      <listitem>
       <para>
	Message returned if the alteration was successful.
       </para>
      </listitem>
     </varlistentry>
     
     <varlistentry>
      <term><computeroutput>
ERROR: alterUser: user "username" does not exist
       </computeroutput></term>
      <listitem>
       <para>
	Error message returned if the specified user is not known to
	the database.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
   </para>
  </refsect2>
 </refsynopsisdiv>

 <refsect1 id="R1-SQL-ALTERUSER-1">
  <refsect1info>
   <date>1998-09-08</date>
  </refsect1info>
  <title>
   Description
  </title>
  <para>
   <command>ALTER USER</command> is used to change the attributes of a user's
   <productname>Postgres</productname> account.
   Also, it is only possible for the
   <productname>Postgres</productname>
   user or any user with read and modify permissions on
   <literal>pg_shadow</literal> to alter user passwords.
  </para>

  <para>
   If any of the clauses of the alter user statement are
   omitted, the corresponding value in the <literal>pg_shadow</literal> table
   is left unchanged.
  </para>
    
  <refsect2 id="R2-SQL-ALTERUSER-3">
   <refsect2info>
    <date>1998-09-08</date>
   </refsect2info>
   <title>
    Notes
   </title>
   <para>
    <command>ALTER USER</command>
    is a <productname>Postgres</productname>
    language extension.
   </para>
   <para>
    Refer to <command>CREATE/DROP USER</command>
    to create or remove a user account.
   </para>
   <para>
    The IN GROUP clause is not yet implemented.
   </para>
  </refsect2>
 </refsect1>

 <refsect1 id="R1-SQL-ALTERUSER-2">
  <title>
   Usage
  </title>
  <para>
   Change a user password:

  <programlisting>
ALTER USER davide WITH PASSWORD hu8jmn3;
  </programlisting>

   Change a user's valid until date

   <programlisting>
ALTER USER manuel VALID UNTIL 'Jan 31 2030';
   </programlisting>

   Change a user's valid until date, specifying that his
   authorisation should expire at midday on 4th May 1998 using
   the time zone which is one hour ahead of UTC
   <programlisting>
ALTER USER chris VALID UNTIL 'May 4 12:00:00 1998 +1';
   </programlisting>

   Give a user the ability to create other users and new databases.

   <programlisting>
ALTER USER miriam CREATEUSER CREATEDB;
   </programlisting>

   Place a user in two groups

   <programlisting>
ALTER USER miriam IN GROUP sales, payroll;
   </programlisting>
  </para>
 </refsect1>

 <refsect1 id="R1-SQL-ALTERUSER-3">
  <title>
   Compatibility
  </title>
    
  <refsect2 id="R2-SQL-ALTERUSER-4">
   <refsect2info>
    <date>1998-09-08</date>
   </refsect2info>
   <title>
    SQL92
   </title>
   <para>
    There is no <command>ALTER USER</command> statement in
    <acronym>SQL92</acronym>.
    The standard leaves
    the definition of users to the implementation.
   </para>
  </refsect2>
 </refsect1>
</refentry>

<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:nil
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
sgml-parent-document:nil
sgml-default-dtd-file:"../reference.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:"/usr/lib/sgml/catalog"
sgml-local-ecat-files:nil
End:
-->
