Sophie: postgresql8.3-docs-8.3.6-2mdv2008.1 x86

postgresql8.3-docs-8.3.6-2mdv2008.1.x86_64.rpm

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><H1
><A
NAME="SQL-SET-ROLE"
></A
>SET ROLE</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN60435"
></A
><H2
>Name</H2
>SET ROLE&nbsp;--&nbsp;set the current user identifier of the current session</DIV
><A
NAME="AEN60438"
></A
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN60440"
></A
><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>SET [ SESSION | LOCAL ] ROLE <TT
CLASS="REPLACEABLE"
><I
>rolename</I
></TT
>
SET [ SESSION | LOCAL ] ROLE NONE
RESET ROLE</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN60443"
></A
><H2
>Description</H2
><P
>   This command sets the current user
   identifier of the current SQL session to be <TT
CLASS="REPLACEABLE"
><I
>rolename</I
></TT
>.  The role name can be
   written as either an identifier or a string literal.
   After <TT
CLASS="COMMAND"
>SET ROLE</TT
>, permissions checking for SQL commands
   is carried out as though the named role were the one that had logged
   in originally.
  </P
><P
>   The specified <TT
CLASS="REPLACEABLE"
><I
>rolename</I
></TT
>
   must be a role that the current session user is a member of.
   (If the session user is a superuser, any role can be selected.)
  </P
><P
>   The <TT
CLASS="LITERAL"
>SESSION</TT
> and <TT
CLASS="LITERAL"
>LOCAL</TT
> modifiers act the same
   as for the regular <A
HREF="sql-set.html"
><I
>SET</I
></A
>
   command.
  </P
><P
>   The <TT
CLASS="LITERAL"
>NONE</TT
> and <TT
CLASS="LITERAL"
>RESET</TT
> forms reset the current
   user identifier to be the current session user identifier.
   These forms can be executed by any user.
  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN60457"
></A
><H2
>Notes</H2
><P
>   Using this command, it is possible to either add privileges or restrict
   one's privileges.  If the session user role has the <TT
CLASS="LITERAL"
>INHERITS</TT
>
   attribute, then it automatically has all the privileges of every role that
   it could <TT
CLASS="COMMAND"
>SET ROLE</TT
> to; in this case <TT
CLASS="COMMAND"
>SET ROLE</TT
>
   effectively drops all the privileges assigned directly to the session user
   and to the other roles it is a member of, leaving only the privileges
   available to the named role.  On the other hand, if the session user role
   has the <TT
CLASS="LITERAL"
>NOINHERITS</TT
> attribute, <TT
CLASS="COMMAND"
>SET ROLE</TT
> drops the
   privileges assigned directly to the session user and instead acquires the
   privileges available to the named role.
  </P
><P
>   In particular, when a superuser chooses to <TT
CLASS="COMMAND"
>SET ROLE</TT
> to a
   non-superuser role, she loses her superuser privileges.
  </P
><P
>   <TT
CLASS="COMMAND"
>SET ROLE</TT
> has effects comparable to
   <A
HREF="sql-set-session-authorization.html"
><I
>SET SESSION AUTHORIZATION</I
></A
>, but the privilege
   checks involved are quite different.  Also,
   <TT
CLASS="COMMAND"
>SET SESSION AUTHORIZATION</TT
> determines which roles are
   allowable for later <TT
CLASS="COMMAND"
>SET ROLE</TT
> commands, whereas changing
   roles with <TT
CLASS="COMMAND"
>SET ROLE</TT
> does not change the set of roles
   allowed to a later <TT
CLASS="COMMAND"
>SET ROLE</TT
>.
  </P
><P
>   <TT
CLASS="COMMAND"
>SET ROLE</TT
> cannot be used within a
   <TT
CLASS="LITERAL"
>SECURITY DEFINER</TT
> function.
  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN60477"
></A
><H2
>Examples</H2
><PRE
CLASS="PROGRAMLISTING"
>SELECT SESSION_USER, CURRENT_USER;

 session_user | current_user 
--------------+--------------
 peter        | peter

SET ROLE 'paul';

SELECT SESSION_USER, CURRENT_USER;

 session_user | current_user 
--------------+--------------
 peter        | paul</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN60480"
></A
><H2
>Compatibility</H2
><P
>   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
>
   allows identifier syntax (<TT
CLASS="LITERAL"
>"rolename"</TT
>), while
   the SQL standard requires the role name to be written as a string
   literal.  SQL does not allow this command during a transaction;
   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> does not make this
   restriction because there is no reason to.
   The <TT
CLASS="LITERAL"
>SESSION</TT
> and <TT
CLASS="LITERAL"
>LOCAL</TT
> modifiers are a
   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> extension, as is the
   <TT
CLASS="LITERAL"
>RESET</TT
> syntax.
  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN60490"
></A
><H2
>See Also</H2
><A
HREF="sql-set-session-authorization.html"
><I
>SET SESSION AUTHORIZATION</I
></A
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