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diff --git a/doc/src/sgml/html/role-membership.html b/doc/src/sgml/html/role-membership.html new file mode 100644 index 0000000..3f2150a --- /dev/null +++ b/doc/src/sgml/html/role-membership.html @@ -0,0 +1,107 @@ +<?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>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 15.5 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</h2></div></div></div><a id="id-1.6.9.7.2" class="indexterm"></a><p> + It is frequently convenient to group users together to ease + management of privileges: that way, privileges can be granted to, or + revoked from, a group as a whole. In <span class="productname">PostgreSQL</span> + this is done by creating a role that represents the group, and then + granting <em class="firstterm">membership</em> in the group role to individual user + roles. + </p><p> + To set up a group role, first create the role: +</p><pre class="synopsis"> +CREATE ROLE <em class="replaceable"><code>name</code></em>; +</pre><p> + Typically a role being used as a group would not have the <code class="literal">LOGIN</code> + attribute, though you can set it if you wish. + </p><p> + Once the group role exists, you can add and remove members using the + <a class="link" href="sql-grant.html" title="GRANT"><code class="command">GRANT</code></a> and + <a class="link" href="sql-revoke.html" title="REVOKE"><code class="command">REVOKE</code></a> commands: +</p><pre class="synopsis"> +GRANT <em class="replaceable"><code>group_role</code></em> TO <em class="replaceable"><code>role1</code></em>, ... ; +REVOKE <em class="replaceable"><code>group_role</code></em> FROM <em class="replaceable"><code>role1</code></em>, ... ; +</pre><p> + You can grant membership to other group roles, too (since there isn't + really any distinction between group roles and non-group roles). The + database will not let you set up circular membership loops. Also, + it is not permitted to grant membership in a role to + <code class="literal">PUBLIC</code>. + </p><p> + The members of a group role can use the privileges of the role in two + ways. First, every member of a group can explicitly do + <a class="link" href="sql-set-role.html" title="SET ROLE"><code class="command">SET ROLE</code></a> to + temporarily <span class="quote">“<span class="quote">become</span>”</span> the group role. In this state, the + database session has access to the privileges of the group role rather + than the original login role, and any database objects created are + considered owned by the group role not the login role. Second, member + roles that have the <code class="literal">INHERIT</code> attribute automatically have use + of the privileges of roles of which they are members, including any + privileges inherited by those roles. + As an example, suppose we have done: +</p><pre class="programlisting"> +CREATE ROLE joe LOGIN INHERIT; +CREATE ROLE admin NOINHERIT; +CREATE ROLE wheel NOINHERIT; +GRANT admin TO joe; +GRANT wheel TO admin; +</pre><p> + Immediately after connecting as role <code class="literal">joe</code>, a database + session will have use of privileges granted directly to <code class="literal">joe</code> + plus any privileges granted to <code class="literal">admin</code>, because <code class="literal">joe</code> + <span class="quote">“<span class="quote">inherits</span>”</span> <code class="literal">admin</code>'s privileges. However, privileges + granted to <code class="literal">wheel</code> are not available, because even though + <code class="literal">joe</code> is indirectly a member of <code class="literal">wheel</code>, the + membership is via <code class="literal">admin</code> which has the <code class="literal">NOINHERIT</code> + attribute. After: +</p><pre class="programlisting"> +SET ROLE admin; +</pre><p> + the session would have use of only those privileges granted to + <code class="literal">admin</code>, and not those granted to <code class="literal">joe</code>. After: +</p><pre class="programlisting"> +SET ROLE wheel; +</pre><p> + the session would have use of only those privileges granted to + <code class="literal">wheel</code>, and not those granted to either <code class="literal">joe</code> + or <code class="literal">admin</code>. The original privilege state can be restored + with any of: +</p><pre class="programlisting"> +SET ROLE joe; +SET ROLE NONE; +RESET ROLE; +</pre><p> + </p><div class="note"><h3 class="title">Note</h3><p> + The <code class="command">SET ROLE</code> command always allows selecting any role + that the original login role is directly or indirectly a member of. + Thus, in the above example, it is not necessary to become + <code class="literal">admin</code> before becoming <code class="literal">wheel</code>. + </p></div><div class="note"><h3 class="title">Note</h3><p> + In the SQL standard, there is a clear distinction between users and roles, + and users do not automatically inherit privileges while roles do. This + behavior can be obtained in <span class="productname">PostgreSQL</span> by giving + roles being used as SQL roles the <code class="literal">INHERIT</code> attribute, while + giving roles being used as SQL users the <code class="literal">NOINHERIT</code> attribute. + However, <span class="productname">PostgreSQL</span> defaults to giving all roles + the <code class="literal">INHERIT</code> attribute, for backward compatibility with pre-8.1 + releases in which users always had use of permissions granted to groups + they were members of. + </p></div><p> + The role attributes <code class="literal">LOGIN</code>, <code class="literal">SUPERUSER</code>, + <code class="literal">CREATEDB</code>, and <code class="literal">CREATEROLE</code> can be thought of as + special privileges, but they are never inherited as ordinary privileges + on database objects are. You must actually <code class="command">SET ROLE</code> to a + specific role having one of these attributes in order to make use of + the attribute. Continuing the above example, we might choose to + grant <code class="literal">CREATEDB</code> and <code class="literal">CREATEROLE</code> to the + <code class="literal">admin</code> role. Then a session connecting as role <code class="literal">joe</code> + would not have these privileges immediately, only after doing + <code class="command">SET ROLE admin</code>. + </p><p> + </p><p> + To destroy a group role, use <a class="link" href="sql-droprole.html" title="DROP ROLE"><code class="command">DROP ROLE</code></a>: +</p><pre class="synopsis"> +DROP ROLE <em class="replaceable"><code>name</code></em>; +</pre><p> + Any memberships in the group role are automatically revoked (but the + member roles are not otherwise affected). + </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 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 22.4. Dropping Roles</td></tr></table></div></body></html>
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