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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >SET ROLE</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="SQL Commands" HREF="sql-commands.html"><LINK REL="PREVIOUS" TITLE="SET CONSTRAINTS" HREF="sql-set-constraints.html"><LINK REL="NEXT" TITLE="SET SESSION AUTHORIZATION" HREF="sql-set-session-authorization.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="SET CONSTRAINTS" HREF="sql-set-constraints.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="SET SESSION AUTHORIZATION" HREF="sql-set-session-authorization.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SQL-SET-ROLE" ></A >SET ROLE</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN78929" ></A ><H2 >Name</H2 >SET ROLE -- set the current user identifier of the current session</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN78934" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >SET [ SESSION | LOCAL ] ROLE <TT CLASS="REPLACEABLE" ><I >role_name</I ></TT > SET [ SESSION | LOCAL ] ROLE NONE RESET ROLE</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN78937" ></A ><H2 >Description</H2 ><P > This command sets the current user identifier of the current SQL session to be <TT CLASS="REPLACEABLE" ><I >role_name</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 >role_name</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" >SET</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="AEN78951" ></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" >SET SESSION AUTHORIZATION</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 > does not process session variables as specified by the role's <A HREF="sql-alterrole.html" >ALTER ROLE</A > settings; this only happens during login. </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="AEN78974" ></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="AEN78977" ></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="AEN78987" ></A ><H2 >See Also</H2 ><A HREF="sql-set-session-authorization.html" >SET SESSION AUTHORIZATION</A ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sql-set-constraints.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sql-set-session-authorization.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SET CONSTRAINTS</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SET SESSION AUTHORIZATION</TD ></TR ></TABLE ></DIV ></BODY ></HTML >