@@ -30,16 +30,10 @@ DISCARD { ALL | PLANS | SEQUENCES | TEMPORARY | TEMP }
3030
3131 <para>
3232 <command>DISCARD</> releases internal resources associated with a
33- database session. These resources are normally released at the end
34- of the session.
35- </para>
36-
37- <para>
38- <command>DISCARD TEMP</> drops all temporary tables created in the
39- current session. <command>DISCARD PLANS</> releases all internally
40- cached query plans. <command>DISCARD ALL</> resets a session to
41- its original state, discarding temporary resources and resetting
42- session-local configuration changes.
33+ database session. This command is useful for partially or fully
34+ resetting the session's state. There are several subcommands to
35+ release different types of resources; the <command>DISCARD ALL</>
36+ variant subsumes all the others, and also resets additional state.
4337 </para>
4438 </refsect1>
4539
@@ -49,28 +43,34 @@ DISCARD { ALL | PLANS | SEQUENCES | TEMPORARY | TEMP }
4943 <variablelist>
5044
5145 <varlistentry>
52- <term><literal>TEMPORARY</literal> or <literal>TEMP </literal></term>
46+ <term><literal>PLANS </literal></term>
5347 <listitem>
5448 <para>
55- Drops all temporary tables created in the current session.
49+ Releases all cached query plans, forcing re-planning to occur
50+ the next time the associated prepared statement is used.
5651 </para>
5752 </listitem>
5853 </varlistentry>
5954
6055 <varlistentry>
61- <term><literal>PLANS </literal></term>
56+ <term><literal>SEQUENCES </literal></term>
6257 <listitem>
6358 <para>
64- Releases all cached query plans.
59+ Discards all cached sequence-related state,
60+ including <function>currval()</>/<function>lastval()</>
61+ information and any preallocated sequence values that have not
62+ yet been returned by <function>nextval()</>.
63+ (See <xref linkend="sql-createsequence"> for a description of
64+ preallocated sequence values.)
6565 </para>
6666 </listitem>
6767 </varlistentry>
6868
6969 <varlistentry>
70- <term><literal>SEQUENCES </literal></term>
70+ <term><literal>TEMPORARY</literal> or <literal>TEMP </literal></term>
7171 <listitem>
7272 <para>
73- Discards allcached sequence values .
73+ Drops alltemporary tables created in the current session .
7474 </para>
7575 </listitem>
7676 </varlistentry>
@@ -91,8 +91,8 @@ CLOSE ALL;
9191UNLISTEN *;
9292SELECT pg_advisory_unlock_all();
9393DISCARD PLANS;
94- DISCARD TEMP;
9594DISCARD SEQUENCES;
95+ DISCARD TEMP;
9696</programlisting></para>
9797 </listitem>
9898 </varlistentry>