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1<?xml version="1.0" encoding="UTF-8" standalone="no"?>2<!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>22.3. Role Membership</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="role-attributes.html" title="22.2. Role Attributes" /><link rel="next" href="role-removal.html" title="22.4. Dropping Roles" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">22.3. Role Membership</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="role-attributes.html" title="22.2. Role Attributes">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="user-manag.html" title="Chapter 22. Database Roles">Up</a></td><th width="60%" align="center">Chapter 22. Database Roles</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="role-removal.html" title="22.4. Dropping Roles">Next</a></td></tr></table><hr /></div><div class="sect1" id="ROLE-MEMBERSHIP"><div class="titlepage"><div><div><h2 class="title" style="clear: both">22.3. Role Membership <a href="#ROLE-MEMBERSHIP" class="id_link">#</a></h2></div></div></div><a id="id-1.6.9.7.2" class="indexterm"></a><p>3   It is frequently convenient to group users together to ease4   management of privileges: that way, privileges can be granted to, or5   revoked from, a group as a whole.  In <span class="productname">PostgreSQL</span>6   this is done by creating a role that represents the group, and then7   granting <em class="firstterm">membership</em> in the group role to individual user8   roles.9  </p><p>10   To set up a group role, first create the role:11</p><pre class="synopsis">12CREATE ROLE <em class="replaceable"><code>name</code></em>;13</pre><p>14   Typically a role being used as a group would not have the <code class="literal">LOGIN</code>15   attribute, though you can set it if you wish.16  </p><p>17   Once the group role exists, you can add and remove members using the18   <a class="link" href="sql-grant.html" title="GRANT"><code class="command">GRANT</code></a> and19   <a class="link" href="sql-revoke.html" title="REVOKE"><code class="command">REVOKE</code></a> commands:20</p><pre class="synopsis">21GRANT <em class="replaceable"><code>group_role</code></em> TO <em class="replaceable"><code>role1</code></em>, ... ;22REVOKE <em class="replaceable"><code>group_role</code></em> FROM <em class="replaceable"><code>role1</code></em>, ... ;23</pre><p>24   You can grant membership to other group roles, too (since there isn't25   really any distinction between group roles and non-group roles).  The26   database will not let you set up circular membership loops.  Also,27   it is not permitted to grant membership in a role to28   <code class="literal">PUBLIC</code>.29  </p><p>30   The members of a group role can use the privileges of the role in two31   ways.  First, member roles that have been granted membership with the32   <code class="literal">SET</code> option can do33   <a class="link" href="sql-set-role.html" title="SET ROLE"><code class="command">SET ROLE</code></a> to34   temporarily <span class="quote">“<span class="quote">become</span>”</span> the group role.  In this state, the35   database session has access to the privileges of the group role rather36   than the original login role, and any database objects created are37   considered owned by the group role not the login role.  Second, member38   roles that have been granted membership with the39   <code class="literal">INHERIT</code> option automatically have use of the40   privileges of those directly or indirectly a member of, though the41   chain stops at memberships lacking the inherit option.  As an example,42   suppose we have done:43</p><pre class="programlisting">44CREATE ROLE joe LOGIN;45CREATE ROLE admin;46CREATE ROLE wheel;47CREATE ROLE island;48GRANT admin TO joe WITH INHERIT TRUE;49GRANT wheel TO admin WITH INHERIT FALSE;50GRANT island TO joe WITH INHERIT TRUE, SET FALSE;51</pre><p>52   Immediately after connecting as role <code class="literal">joe</code>, a database53   session will have use of privileges granted directly to <code class="literal">joe</code>54   plus any privileges granted to <code class="literal">admin</code> and55   <code class="literal">island</code>, because <code class="literal">joe</code>56   <span class="quote">“<span class="quote">inherits</span>”</span> those privileges.  However, privileges57   granted to <code class="literal">wheel</code> are not available, because even though58   <code class="literal">joe</code> is indirectly a member of <code class="literal">wheel</code>, the59   membership is via <code class="literal">admin</code> which was granted using60   <code class="literal">WITH INHERIT FALSE</code>. After:61</p><pre class="programlisting">62SET ROLE admin;63</pre><p>64   the session would have use of only those privileges granted to65   <code class="literal">admin</code>, and not those granted to <code class="literal">joe</code> or66   <code class="literal">island</code>.  After:67</p><pre class="programlisting">68SET ROLE wheel;69</pre><p>70   the session would have use of only those privileges granted to71   <code class="literal">wheel</code>, and not those granted to either <code class="literal">joe</code>72   or <code class="literal">admin</code>.  The original privilege state can be restored73   with any of:74</p><pre class="programlisting">75SET ROLE joe;76SET ROLE NONE;77RESET ROLE;78</pre><p>79  </p><div class="note"><h3 class="title">Note</h3><p>80    The <code class="command">SET ROLE</code> command always allows selecting any role81    that the original login role is directly or indirectly a member of,82    provided that there is a chain of membership grants each of which has83    <code class="literal">SET TRUE</code> (which is the default).84    Thus, in the above example, it is not necessary to become85    <code class="literal">admin</code> before becoming <code class="literal">wheel</code>.86    On the other hand, it is not possible to become <code class="literal">island</code>87    at all; <code class="literal">joe</code> can only access those privileges via88    inheritance.89   </p></div><div class="note"><h3 class="title">Note</h3><p>90    In the SQL standard, there is a clear distinction between users and roles,91    and users do not automatically inherit privileges while roles do.  This92    behavior can be obtained in <span class="productname">PostgreSQL</span> by giving93    roles being used as SQL roles the <code class="literal">INHERIT</code> attribute, while94    giving roles being used as SQL users the <code class="literal">NOINHERIT</code> attribute.95    However, <span class="productname">PostgreSQL</span> defaults to giving all roles96    the <code class="literal">INHERIT</code> attribute, for backward compatibility with pre-8.197    releases in which users always had use of permissions granted to groups98    they were members of.99   </p></div><p>100   The role attributes <code class="literal">LOGIN</code>, <code class="literal">SUPERUSER</code>,101   <code class="literal">CREATEDB</code>, and <code class="literal">CREATEROLE</code> can be thought of as102   special privileges, but they are never inherited as ordinary privileges103   on database objects are.  You must actually <code class="command">SET ROLE</code> to a104   specific role having one of these attributes in order to make use of105   the attribute.  Continuing the above example, we might choose to106   grant <code class="literal">CREATEDB</code> and <code class="literal">CREATEROLE</code> to the107   <code class="literal">admin</code> role.  Then a session connecting as role <code class="literal">joe</code>108   would not have these privileges immediately, only after doing109   <code class="command">SET ROLE admin</code>.110  </p><p>111  </p><p>112   To destroy a group role, use <a class="link" href="sql-droprole.html" title="DROP ROLE"><code class="command">DROP ROLE</code></a>:113</p><pre class="synopsis">114DROP ROLE <em class="replaceable"><code>name</code></em>;115</pre><p>116   Any memberships in the group role are automatically revoked (but the117   member roles are not otherwise affected).118  </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="role-attributes.html" title="22.2. Role Attributes">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="user-manag.html" title="Chapter 22. Database Roles">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="role-removal.html" title="22.4. Dropping Roles">Next</a></td></tr><tr><td width="40%" align="left" valign="top">22.2. Role Attributes </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"> 22.4. Dropping Roles</td></tr></table></div></body></html>