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<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>SET ROLE</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="sql-set-constraints.html" title="SET CONSTRAINTS" /><link rel="next" href="sql-set-session-authorization.html" title="SET SESSION AUTHORIZATION" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">SET ROLE</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-set-constraints.html" title="SET CONSTRAINTS">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-set-session-authorization.html" title="SET SESSION AUTHORIZATION">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-SET-ROLE"><div class="titlepage"></div><a id="id-1.9.3.176.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">SET ROLE</span></h2><p>SET ROLE — set the current user identifier of the current session</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> SET [ SESSION | LOCAL ] ROLE <em class="replaceable"><code>role_name</code></em> SET [ SESSION | LOCAL ] ROLE NONE RESET ROLE </pre></div><div class="refsect1" id="id-1.9.3.176.5"><h2>Description</h2><p> This command sets the current user identifier of the current SQL session to be <em class="replaceable"><code>role_name</code></em>. The role name can be written as either an identifier or a string literal. After <code class="command">SET ROLE</code>, permissions checking for SQL commands is carried out as though the named role were the one that had logged in originally. </p><p> The current session user must have the <code class="literal">SET</code> option for the specified <em class="replaceable"><code>role_name</code></em>, either directly or indirectly via a chain of memberships with the <code class="literal">SET</code> option. (If the session user is a superuser, any role can be selected.) </p><p> The <code class="literal">SESSION</code> and <code class="literal">LOCAL</code> modifiers act the same as for the regular <a class="link" href="sql-set.html" title="SET"><code class="command">SET</code></a> command. </p><p> <code class="literal">SET ROLE NONE</code> sets the current user identifier to the current session user identifier, as returned by <code class="function">session_user</code>. <code class="literal">RESET ROLE</code> sets the current user identifier to the connection-time setting specified by the <a class="link" href="libpq-connect.html#LIBPQ-CONNECT-OPTIONS">command-line options</a>, <a class="link" href="sql-alterrole.html" title="ALTER ROLE"><code class="command">ALTER ROLE</code></a>, or <a class="link" href="sql-alterdatabase.html" title="ALTER DATABASE"><code class="command">ALTER DATABASE</code></a>, if any such settings exist. Otherwise, <code class="literal">RESET ROLE</code> sets the current user identifier to the current session user identifier. These forms can be executed by any user. </p></div><div class="refsect1" id="id-1.9.3.176.6"><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 been granted memberships <code class="literal">WITH INHERIT TRUE</code>, it automatically has all the privileges of every such role. In this case, <code class="command">SET ROLE</code> effectively drops all the privileges except for those which the target role directly possesses or inherits. On the other hand, if the session user role has been granted memberships <code class="literal">WITH INHERIT FALSE</code>, the privileges of the granted roles can't be accessed by default. However, if the role was granted <code class="literal">WITH SET TRUE</code>, the session user can use <code class="command">SET ROLE</code> to drop the privileges assigned directly to the session user and instead acquire the privileges available to the named role. If the role was granted <code class="literal">WITH INHERIT FALSE, SET FALSE</code> then the privileges of that role cannot be exercised either with or without <code class="literal">SET ROLE</code>. </p><p> Note that when a superuser chooses to <code class="command">SET ROLE</code> to a non-superuser role, they lose their superuser privileges. </p><p> <code class="command">SET ROLE</code> has effects comparable to <a class="link" href="sql-set-session-authorization.html" title="SET SESSION AUTHORIZATION"><code class="command">SET SESSION AUTHORIZATION</code></a>, but the privilege checks involved are quite different. Also, <code class="command">SET SESSION AUTHORIZATION</code> determines which roles are allowable for later <code class="command">SET ROLE</code> commands, whereas changing roles with <code class="command">SET ROLE</code> does not change the set of roles allowed to a later <code class="command">SET ROLE</code>. </p><p> <code class="command">SET ROLE</code> does not process session variables as specified by the role's <a class="link" href="sql-alterrole.html" title="ALTER ROLE"><code class="command">ALTER ROLE</code></a> settings; this only happens during login. </p><p> <code class="command">SET ROLE</code> cannot be used within a <code class="literal">SECURITY DEFINER</code> function. </p></div><div class="refsect1" id="id-1.9.3.176.7"><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" id="id-1.9.3.176.8"><h2>Compatibility</h2><p> <span class="productname">PostgreSQL</span> allows identifier syntax (<code class="literal">"<em class="replaceable"><code>rolename</code></em>"</code>), 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 <code class="literal">SESSION</code> and <code class="literal">LOCAL</code> modifiers are a <span class="productname">PostgreSQL</span> extension, as is the <code class="literal">RESET</code> syntax. </p></div><div class="refsect1" id="id-1.9.3.176.9"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-set-session-authorization.html" title="SET SESSION AUTHORIZATION"><span class="refentrytitle">SET SESSION AUTHORIZATION</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-set-constraints.html" title="SET CONSTRAINTS">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-set-session-authorization.html" title="SET SESSION AUTHORIZATION">Next</a></td></tr><tr><td width="40%" align="left" valign="top">SET CONSTRAINTS </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> SET SESSION AUTHORIZATION</td></tr></table></div></body></html>