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<refentry id="SQL-REVOKE">
 <refmeta>
  <refentrytitle id="sql-revoke-title">REVOKE</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>REVOKE</refname>
  <refpurpose>remove access privileges</refpurpose>
 </refnamediv>

 <indexterm zone="sql-revoke">
  <primary>REVOKE</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
REVOKE [ GRANT OPTION FOR ]
    { { SELECT | INSERT | UPDATE | DELETE | RULE | REFERENCES | TRIGGER }
    [,...] | ALL [ PRIVILEGES ] }
    ON [ TABLE ] <replaceable class="PARAMETER">tablename</replaceable> [, ...]
    FROM { <replaceable class="PARAMETER">username</replaceable> | GROUP <replaceable class="PARAMETER">groupname</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { { CREATE | TEMPORARY | TEMP } [,...] | ALL [ PRIVILEGES ] }
    ON DATABASE <replaceable>dbname</replaceable> [, ...]
    FROM { <replaceable class="PARAMETER">username</replaceable> | GROUP <replaceable class="PARAMETER">groupname</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { EXECUTE | ALL [ PRIVILEGES ] }
    ON FUNCTION <replaceable>funcname</replaceable> ([<replaceable>type</replaceable>, ...]) [, ...]
    FROM { <replaceable class="PARAMETER">username</replaceable> | GROUP <replaceable class="PARAMETER">groupname</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { USAGE | ALL [ PRIVILEGES ] }
    ON LANGUAGE <replaceable>langname</replaceable> [, ...]
    FROM { <replaceable class="PARAMETER">username</replaceable> | GROUP <replaceable class="PARAMETER">groupname</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { { CREATE | USAGE } [,...] | ALL [ PRIVILEGES ] }
    ON SCHEMA <replaceable>schemaname</replaceable> [, ...]
    FROM { <replaceable class="PARAMETER">username</replaceable> | GROUP <replaceable class="PARAMETER">groupname</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]
</synopsis>
 </refsynopsisdiv>

 <refsect1 id="SQL-REVOKE-description">
  <title>Description</title>

  <para>
   The <command>REVOKE</command> command revokes previously granted
   privileges from one or more users or groups of users.  The key word
   <literal>PUBLIC</literal> refers to the implicitly defined group of
   all users.
  </para>

  <para>
   See the description of the <xref linkend="sql-grant" endterm="sql-grant-title"> command for
   the meaning of the privilege types.
  </para>

  <para>
   Note that any particular user will have the sum
   of privileges granted directly to him, privileges granted to any group he
   is presently a member of, and privileges granted to
   <literal>PUBLIC</literal>.  Thus, for example, revoking <literal>SELECT</> privilege
   from <literal>PUBLIC</literal> does not necessarily mean that all users
   have lost <literal>SELECT</> privilege on the object: those who have it granted
   directly or via a group will still have it.
  </para>

  <para>
   If <literal>GRANT OPTION FOR</literal> is specified, only the grant
   option for the privilege is revoked, not the privilege itself.
   Otherwise, both the privilege and the grant option are revoked.
  </para>

  <para>
   If a user holds a privilege with grant option and has granted it to
   other users then the privileges held by those other users are
   called dependent privileges. If the privilege or the grant option
   held by the first user is being revoked and dependent privileges
   exist, those dependent privileges are also revoked if
   <literal>CASCADE</literal> is specified, else the revoke action
   will fail.  This recursive revocation only affects privileges that
   were granted through a chain of users that is traceable to the user
   that is the subject of this <literal>REVOKE</literal> command.
   Thus, the affected users may effectively keep the privilege if it
   was also granted through other users.
  </para>
 </refsect1>

 <refsect1 id="SQL-REVOKE-notes">
  <title>Notes</title>

  <para>
   Use <xref linkend="app-psql">'s <command>\z</command> command to
   display the privileges granted on existing objects.  See <xref
   linkend="sql-grant" endterm="sql-grant-title"> for information about the format.
  </para>

  <para>
   A user can only revoke privileges that were granted directly by
   that user.  If, for example, user A has granted a privilege with
   grant option to user B, and user B has in turned granted it to user
   C, then user A cannot revoke the privilege directly from C.
   Instead, user A could revoke the grant option from user B and use
   the <literal>CASCADE</literal> option so that the privilege is
   in turn revoked from user C.  For another example, if both A and B
   have granted the same privilege to C, A can revoke his own grant
   but not B's grant, so C will still effectively have the privilege.
  </para>

   <para>
    When a non-owner of an object attempts to <command>REVOKE</> privileges
    on the object, the command will fail outright if the user has no
    privileges whatsoever on the object.  As long as some privilege is
    available, the command will proceed, but it will revoke only those
    privileges for which the user has grant options.  The <command>REVOKE ALL
    PRIVILEGES</> forms will issue a warning message if no grant options are
    held, while the other forms will issue a warning if grant options for
    any of the privileges specifically named in the command are not held.
    (In principle these statements apply to the object owner as well, but
    since the owner is always treated as holding all grant options, the
    cases can never occur.)
   </para>

   <para>
    If a superuser chooses to issue a <command>GRANT</> or <command>REVOKE</>
    command, the command is performed as though it were issued by the
    owner of the affected object.  Since all privileges ultimately come
    from the object owner (possibly indirectly via chains of grant options),
    it is possible for a superuser to revoke all privileges, but this may
    require use of <literal>CASCADE</literal> as stated above.
   </para>
 </refsect1>

 <refsect1 id="SQL-REVOKE-examples">
  <title>Examples</title>

  <para>
   Revoke insert privilege for the public on table
   <literal>films</literal>:

<programlisting>
REVOKE INSERT ON films FROM PUBLIC;
</programlisting>
  </para>

  <para>
   Revoke all privileges from user <literal>manuel</literal> on view
   <literal>kinds</literal>:

<programlisting>
REVOKE ALL PRIVILEGES ON kinds FROM manuel;
</programlisting>

   Note that this actually means <quote>revoke all privileges that I
   granted</>.
  </para>
 </refsect1>

 <refsect1 id="SQL-REVOKE-compatibility">
  <title>Compatibility</title>

   <para>
    The compatibility notes of the <xref linkend="sql-grant" endterm="sql-grant-title"> command
    apply analogously to <command>REVOKE</command>.  The syntax summary is:

<synopsis>
REVOKE [ GRANT OPTION FOR ] <replaceable class="PARAMETER">privileges</replaceable>
    ON <replaceable class="parameter">object</replaceable> [ ( <replaceable class="parameter">column</replaceable> [, ...] ) ]
    FROM { PUBLIC | <replaceable class="parameter">username</replaceable> [, ...] }
    { RESTRICT | CASCADE }
</synopsis>
    One of <literal>RESTRICT</literal> or <literal>CASCADE</literal>
    is required according to the standard, but <productname>PostgreSQL</>
    assumes <literal>RESTRICT</literal> by default.
   </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <simpara>
   <xref linkend="sql-grant" endterm="sql-grant-title">
  </simpara>
 </refsect1>

</refentry>

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