Fix xslt_process() to ensure that it inserts a NULL terminator after the
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1 <!--
2 $PostgreSQL$
3 PostgreSQL documentation
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6 <refentry id="SQL-ALTERROLE">
7 <refmeta>
8 <refentrytitle id="sql-alterrole-title">ALTER ROLE</refentrytitle>
9 <manvolnum>7</manvolnum>
10 <refmiscinfo>SQL - Language Statements</refmiscinfo>
11 </refmeta>
13 <refnamediv>
14 <refname>ALTER ROLE</refname>
15 <refpurpose>change a database role</refpurpose>
16 </refnamediv>
18 <indexterm zone="sql-alterrole">
19 <primary>ALTER ROLE</primary>
20 </indexterm>
22 <refsynopsisdiv>
23 <synopsis>
24 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <replaceable class="PARAMETER">option</replaceable> [ ... ] ]
26 where <replaceable class="PARAMETER">option</replaceable> can be:
28 SUPERUSER | NOSUPERUSER
29 | CREATEDB | NOCREATEDB
30 | CREATEROLE | NOCREATEROLE
31 | CREATEUSER | NOCREATEUSER
32 | INHERIT | NOINHERIT
33 | LOGIN | NOLOGIN
34 | CONNECTION LIMIT <replaceable class="PARAMETER">connlimit</replaceable>
35 | [ ENCRYPTED | UNENCRYPTED ] PASSWORD '<replaceable class="PARAMETER">password</replaceable>'
36 | VALID UNTIL '<replaceable class="PARAMETER">timestamp</replaceable>'
38 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable>newname</replaceable>
40 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> SET <replaceable>configuration_parameter</replaceable> { TO | = } { <replaceable>value</replaceable> | DEFAULT }
41 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> SET <replaceable>configuration_parameter</replaceable> FROM CURRENT
42 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> RESET <replaceable>configuration_parameter</replaceable>
43 ALTER ROLE <replaceable class="PARAMETER">name</replaceable> RESET ALL
44 </synopsis>
45 </refsynopsisdiv>
47 <refsect1>
48 <title>Description</title>
50 <para>
51 <command>ALTER ROLE</command> changes the attributes of a
52 <productname>PostgreSQL</productname> role.
53 </para>
55 <para>
56 The first variant of this command listed in the synopsis can change
57 many of the role attributes that can be specified in
58 <xref linkend="sql-createrole" endterm="sql-createrole-title">.
59 (All the possible attributes are covered,
60 except that there are no options for adding or removing memberships; use
61 <xref linkend="SQL-GRANT" endterm="SQL-GRANT-title"> and
62 <xref linkend="SQL-REVOKE" endterm="SQL-REVOKE-title"> for that.)
63 Attributes not mentioned in the command retain their previous settings.
64 Database superusers can change any of these settings for any role.
65 Roles having <literal>CREATEROLE</> privilege can change any of these
66 settings, but only for non-superuser roles.
67 Ordinary roles can only change their own password.
68 </para>
70 <para>
71 The second variant changes the name of the role.
72 Database superusers can rename any role.
73 Roles having <literal>CREATEROLE</> privilege can rename non-superuser
74 roles.
75 The current session user cannot be renamed.
76 (Connect as a different user if you need to do that.)
77 Because <literal>MD5</>-encrypted passwords use the role name as
78 cryptographic salt, renaming a role clears its password if the
79 password is <literal>MD5</>-encrypted.
80 </para>
82 <para>
83 The remaining variants change a role's session default for a
84 specified configuration variable. Whenever the role subsequently
85 starts a new session, the specified value becomes the session
86 default, overriding whatever setting is present in
87 <filename>postgresql.conf</> or has been received from the postgres
88 command line. This only happens at login time, so configuration
89 settings associated with a role to which you've <xref
90 linkend="sql-set-role" endterm="sql-set-role-title"> will be ignored.
91 Superusers can change anyone's session defaults. Roles having
92 <literal>CREATEROLE</> privilege can change defaults for non-superuser
93 roles. Certain variables cannot be set this way, or can only be
94 set if a superuser issues the command.
95 </para>
96 </refsect1>
98 <refsect1>
99 <title>Parameters</title>
101 <variablelist>
102 <varlistentry>
103 <term><replaceable class="PARAMETER">name</replaceable></term>
104 <listitem>
105 <para>
106 The name of the role whose attributes are to be altered.
107 </para>
108 </listitem>
109 </varlistentry>
111 <varlistentry>
112 <term><literal>SUPERUSER</literal></term>
113 <term><literal>NOSUPERUSER</literal></term>
114 <term><literal>CREATEDB</></term>
115 <term><literal>NOCREATEDB</></term>
116 <term><literal>CREATEROLE</literal></term>
117 <term><literal>NOCREATEROLE</literal></term>
118 <term><literal>CREATEUSER</literal></term>
119 <term><literal>NOCREATEUSER</literal></term>
120 <term><literal>INHERIT</literal></term>
121 <term><literal>NOINHERIT</literal></term>
122 <term><literal>LOGIN</literal></term>
123 <term><literal>NOLOGIN</literal></term>
124 <term><literal>CONNECTION LIMIT</literal> <replaceable class="parameter">connlimit</replaceable></term>
125 <term><literal>PASSWORD</> <replaceable class="parameter">password</replaceable></term>
126 <term><literal>ENCRYPTED</></term>
127 <term><literal>UNENCRYPTED</></term>
128 <term><literal>VALID UNTIL</literal> '<replaceable class="parameter">timestamp</replaceable>'</term>
129 <listitem>
130 <para>
131 These clauses alter attributes originally set by
132 <xref linkend="SQL-CREATEROLE"
133 endterm="SQL-CREATEROLE-title">. For more information, see the
134 <command>CREATE ROLE</command> reference page.
135 </para>
136 </listitem>
137 </varlistentry>
139 <varlistentry>
140 <term><replaceable>newname</replaceable></term>
141 <listitem>
142 <para>
143 The new name of the role.
144 </para>
145 </listitem>
146 </varlistentry>
148 <varlistentry>
149 <term><replaceable>configuration_parameter</replaceable></term>
150 <term><replaceable>value</replaceable></term>
151 <listitem>
152 <para>
153 Set this role's session default for the specified configuration
154 parameter to the given value. If
155 <replaceable>value</replaceable> is <literal>DEFAULT</literal>
156 or, equivalently, <literal>RESET</literal> is used, the
157 role-specific variable setting is removed, so the role will
158 inherit the system-wide default setting in new sessions. Use
159 <literal>RESET ALL</literal> to clear all role-specific settings.
160 <literal>SET FROM CURRENT</> saves the session's current value of
161 the parameter as the role-specific value.
162 </para>
164 <para>
165 Role-specific variable setting take effect only at login;
166 <xref linkend="sql-set-role" endterm="sql-set-role-title">
167 does not process role-specific variable settings.
168 </para>
170 <para>
171 See <xref linkend="sql-set" endterm="sql-set-title"> and <xref
172 linkend="runtime-config"> for more information about allowed
173 parameter names and values.
174 </para>
175 </listitem>
176 </varlistentry>
177 </variablelist>
178 </refsect1>
180 <refsect1>
181 <title>Notes</title>
183 <para>
184 Use <xref linkend="SQL-CREATEROLE" endterm="SQL-CREATEROLE-title">
185 to add new roles, and <xref linkend="SQL-DROPROLE"
186 endterm="SQL-DROPROLE-title"> to remove a role.
187 </para>
189 <para>
190 <command>ALTER ROLE</command> cannot change a role's memberships.
191 Use <xref linkend="SQL-GRANT" endterm="SQL-GRANT-title"> and
192 <xref linkend="SQL-REVOKE" endterm="SQL-REVOKE-title">
193 to do that.
194 </para>
196 <para>
197 Caution must be exercised when specifying an unencrypted password
198 with this command. The password will be transmitted to the server
199 in cleartext, and it might also be logged in the client's command
200 history or the server log. <xref linkend="app-psql"
201 endterm="app-psql-title"> contains a command
202 <command>\password</command> that can be used to safely change a
203 role's password.
204 </para>
206 <para>
207 It is also possible to tie a
208 session default to a specific database rather than to a role; see
209 <xref linkend="sql-alterdatabase" endterm="sql-alterdatabase-title">.
210 Role-specific settings override database-specific
211 ones if there is a conflict.
212 </para>
213 </refsect1>
215 <refsect1>
216 <title>Examples</title>
218 <para>
219 Change a role's password:
221 <programlisting>
222 ALTER ROLE davide WITH PASSWORD 'hu8jmn3';
223 </programlisting>
224 </para>
226 <para>
227 Remove a role's password:
229 <programlisting>
230 ALTER ROLE davide WITH PASSWORD NULL;
231 </programlisting>
232 </para>
234 <para>
235 Change a password expiration date, specifying that the password
236 should expire at midday on 4th May 2015 using
237 the time zone which is one hour ahead of <acronym>UTC</>:
238 <programlisting>
239 ALTER ROLE chris VALID UNTIL 'May 4 12:00:00 2015 +1';
240 </programlisting>
241 </para>
243 <para>
244 Make a password valid forever:
245 <programlisting>
246 ALTER ROLE fred VALID UNTIL 'infinity';
247 </programlisting>
248 </para>
250 <para>
251 Give a role the ability to create other roles and new databases:
253 <programlisting>
254 ALTER ROLE miriam CREATEROLE CREATEDB;
255 </programlisting>
256 </para>
258 <para>
259 Give a role a non-default setting of the
260 <xref linkend="guc-maintenance-work-mem"> parameter:
262 <programlisting>
263 ALTER ROLE worker_bee SET maintenance_work_mem = 100000;
264 </programlisting>
265 </para>
266 </refsect1>
268 <refsect1>
269 <title>Compatibility</title>
271 <para>
272 The <command>ALTER ROLE</command> statement is a
273 <productname>PostgreSQL</productname> extension.
274 </para>
275 </refsect1>
277 <refsect1>
278 <title>See Also</title>
280 <simplelist type="inline">
281 <member><xref linkend="sql-createrole" endterm="sql-createrole-title"></member>
282 <member><xref linkend="sql-droprole" endterm="sql-droprole-title"></member>
283 <member><xref linkend="sql-set" endterm="sql-set-title"></member>
284 </simplelist>
285 </refsect1>
286 </refentry>