doc/src/sgml/ref/alter_default_privileges.sgml - master - githubmirror/postgres

doc/src/sgml/ref/alter_default_privileges.sgml
278 строк10 KB
Fujii Masao
Extend ALTER DEFAULT PRIVILEGES to define default privileges for large objects.
04 апр 2025, 13:02
04 апр 2025, 13:020d6c477
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<refentry id="sql-alterdefaultprivileges">
 <indexterm zone="sql-alterdefaultprivileges">
  <primary>ALTER DEFAULT PRIVILEGES</primary>
 </indexterm>

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

 <refnamediv>
  <refname>ALTER DEFAULT PRIVILEGES</refname>
  <refpurpose>define default access privileges</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
ALTER DEFAULT PRIVILEGES
    [ FOR { ROLE | USER } <replaceable>target_role</replaceable> [, ...] ]
    [ IN SCHEMA <replaceable>schema_name</replaceable> [, ...] ]
    <replaceable class="parameter">abbreviated_grant_or_revoke</replaceable>

<phrase>where <replaceable class="parameter">abbreviated_grant_or_revoke</replaceable> is one of:</phrase>

GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER | MAINTAIN }
    [, ...] | ALL [ PRIVILEGES ] }
    ON TABLES
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { { USAGE | SELECT | UPDATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON SEQUENCES
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { EXECUTE | ALL [ PRIVILEGES ] }
    ON { FUNCTIONS | ROUTINES }
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { USAGE | ALL [ PRIVILEGES ] }
    ON TYPES
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { { USAGE | CREATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON SCHEMAS
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

GRANT { { SELECT | UPDATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON LARGE OBJECTS
    TO { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...] [ WITH GRANT OPTION ]

REVOKE [ GRANT OPTION FOR ]
    { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER | MAINTAIN }
    [, ...] | ALL [ PRIVILEGES ] }
    ON TABLES
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { { USAGE | SELECT | UPDATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON SEQUENCES
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { EXECUTE | ALL [ PRIVILEGES ] }
    ON { FUNCTIONS | ROUTINES }
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { USAGE | ALL [ PRIVILEGES ] }
    ON TYPES
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { { USAGE | CREATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON SCHEMAS
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]

REVOKE [ GRANT OPTION FOR ]
    { { SELECT | UPDATE }
    [, ...] | ALL [ PRIVILEGES ] }
    ON LARGE OBJECTS
    FROM { [ GROUP ] <replaceable class="parameter">role_name</replaceable> | PUBLIC } [, ...]
    [ CASCADE | RESTRICT ]
</synopsis>
 </refsynopsisdiv>

 <refsect1 id="sql-alterdefaultprivileges-description">
  <title>Description</title>

  <para>
   <command>ALTER DEFAULT PRIVILEGES</command> allows you to set the
   privileges that will be applied to objects created in the future.
   (It does not affect privileges assigned to already-existing objects.)
   Privileges can be set globally (i.e., for all objects created in the
   current database), or just for objects created in specified schemas.
  </para>

  <para>
   While you can change your own default privileges and the defaults of
   roles that you are a member of, at object creation time, new object
   permissions are only affected by the default privileges of the current
   role, and are not inherited from any roles in which the current role
   is a member.
  </para>

  <para>
   As explained in <xref linkend="ddl-priv"/>,
   the default privileges for any object type normally grant all grantable
   permissions to the object owner, and may grant some privileges to
   <literal>PUBLIC</literal> as well.  However, this behavior can be changed by
   altering the global default privileges with
   <command>ALTER DEFAULT PRIVILEGES</command>.
  </para>

  <para>
   Currently,
   only the privileges for schemas, tables (including views and foreign
   tables), sequences, functions, types (including domains), and large objects
   can be altered.  For this command, functions include aggregates and procedures.
   The words <literal>FUNCTIONS</literal> and <literal>ROUTINES</literal> are
   equivalent in this command.  (<literal>ROUTINES</literal> is preferred
   going forward as the standard term for functions and procedures taken
   together.  In earlier PostgreSQL releases, only the
   word <literal>FUNCTIONS</literal> was allowed.  It is not possible to set
   default privileges for functions and procedures separately.)
  </para>

  <para>
   Default privileges that are specified per-schema are added to whatever
   the global default privileges are for the particular object type.
   This means you cannot revoke privileges per-schema if they are granted
   globally (either by default, or according to a previous <command>ALTER
   DEFAULT PRIVILEGES</command> command that did not specify a schema).
   Per-schema <literal>REVOKE</literal> is only useful to reverse the
   effects of a previous per-schema <literal>GRANT</literal>.
  </para>

 <refsect2>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><replaceable>target_role</replaceable></term>
    <listitem>
     <para>
      Change default privileges for objects created by the
      <replaceable>target_role</replaceable>, or the current
      role if unspecified.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable>schema_name</replaceable></term>
    <listitem>
     <para>
      The name of an existing schema.  If specified, the default privileges
      are altered for objects later created in that schema.
      If <literal>IN SCHEMA</literal> is omitted, the global default privileges
      are altered.
      <literal>IN SCHEMA</literal> is not allowed when setting privileges
      for schemas and large objects, since schemas can't be nested and
      large objects don't belong to a schema.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable>role_name</replaceable></term>
    <listitem>
     <para>
      The name of an existing role to grant or revoke privileges for.
      This parameter, and all the other parameters in
      <replaceable class="parameter">abbreviated_grant_or_revoke</replaceable>,
      act as described under
      <xref linkend="sql-grant"/> or
      <xref linkend="sql-revoke"/>,
      except that one is setting permissions for a whole class of objects
      rather than specific named objects.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect2>
 </refsect1>

 <refsect1 id="sql-alterdefaultprivileges-notes">
  <title>Notes</title>

  <para>
   Use <xref linkend="app-psql"/>'s <command>\ddp</command> command
   to obtain information about existing assignments of default privileges.
   The meaning of the privilege display is the same as explained for
   <command>\dp</command> in <xref linkend="ddl-priv"/>.
  </para>

  <para>
   If you wish to drop a role for which the default privileges have been
   altered, it is necessary to reverse the changes in its default privileges
   or use <command>DROP OWNED BY</command> to get rid of the default privileges entry
   for the role.
  </para>
 </refsect1>

 <refsect1 id="sql-alterdefaultprivileges-examples">
  <title>Examples</title>

  <para>
   Grant SELECT privilege to everyone for all tables (and views) you
   subsequently create in schema <literal>myschema</literal>, and allow
   role <literal>webuser</literal> to INSERT into them too:

<programlisting>
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema GRANT SELECT ON TABLES TO PUBLIC;
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema GRANT INSERT ON TABLES TO webuser;
</programlisting>
  </para>

  <para>
   Undo the above, so that subsequently-created tables won't have any
   more permissions than normal:

<programlisting>
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema REVOKE SELECT ON TABLES FROM PUBLIC;
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema REVOKE INSERT ON TABLES FROM webuser;
</programlisting>
  </para>

  <para>
   Remove the public EXECUTE permission that is normally granted on functions,
   for all functions subsequently created by role <literal>admin</literal>:
<programlisting>
ALTER DEFAULT PRIVILEGES FOR ROLE admin REVOKE EXECUTE ON FUNCTIONS FROM PUBLIC;
</programlisting>
   Note however that you <emphasis>cannot</emphasis> accomplish that effect
   with a command limited to a single schema.  This command has no effect,
   unless it is undoing a matching <literal>GRANT</literal>:
<programlisting>
ALTER DEFAULT PRIVILEGES IN SCHEMA public REVOKE EXECUTE ON FUNCTIONS FROM PUBLIC;
</programlisting>
   That's because per-schema default privileges can only add privileges to
   the global setting, not remove privileges granted by it.
  </para>
 </refsect1>

 <refsect1>
  <title>Compatibility</title>

  <para>
   There is no <command>ALTER DEFAULT PRIVILEGES</command> statement in the SQL
   standard.
  </para>
 </refsect1>

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

  <simplelist type="inline">
   <member><xref linkend="sql-grant"/></member>
   <member><xref linkend="sql-revoke"/></member>
  </simplelist>
 </refsect1>

</refentry>