diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2008-11-16 17:34:28 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2008-11-16 17:34:28 +0000 |
| commit | 18004101acb98d8fefe7dda1c9f010cceff83b6d (patch) | |
| tree | 2c9436b642ca63f2b831ba4e3cfd16d34436e6a2 /doc/src/sgml/ref/delete.sgml | |
| parent | 30f272a79b248fea1f25d63a3648d2660d370a69 (diff) | |
Modify UPDATE/DELETE WHERE CURRENT OF to use the FOR UPDATE infrastructure to
locate the target row, if the cursor was declared with FOR UPDATE or FOR
SHARE. This approach is more flexible and reliable than digging through the
plan tree; for instance it can cope with join cursors. But we still provide
the old code for use with non-FOR-UPDATE cursors. Per gripe from Robert Haas.
Diffstat (limited to 'doc/src/sgml/ref/delete.sgml')
| -rw-r--r-- | doc/src/sgml/ref/delete.sgml | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/doc/src/sgml/ref/delete.sgml b/doc/src/sgml/ref/delete.sgml index 6c9fdac5033..62e4555614f 100644 --- a/doc/src/sgml/ref/delete.sgml +++ b/doc/src/sgml/ref/delete.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/ref/delete.sgml,v 1.34 2008/11/14 10:22:46 petere Exp $ +$PostgreSQL: pgsql/doc/src/sgml/ref/delete.sgml,v 1.35 2008/11/16 17:34:28 tgl Exp $ PostgreSQL documentation --> @@ -148,10 +148,13 @@ DELETE FROM [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ [ AS ] <para> The name of the cursor to use in a <literal>WHERE CURRENT OF</> condition. The row to be deleted is the one most recently fetched - from this cursor. The cursor must be a simple (non-join, non-aggregate) + from this cursor. The cursor must be a non-grouping query on the <command>DELETE</>'s target table. Note that <literal>WHERE CURRENT OF</> cannot be - specified together with a Boolean condition. + specified together with a Boolean condition. See + <xref linkend="sql-declare" endterm="sql-declare-title"> + for more information about using cursors with + <literal>WHERE CURRENT OF</>. </para> </listitem> </varlistentry> @@ -244,14 +247,14 @@ DELETE FROM films WHERE kind <> 'Musical'; Clear the table <literal>films</literal>: <programlisting> DELETE FROM films; -</programlisting> +</programlisting> </para> <para> Delete completed tasks, returning full details of the deleted rows: <programlisting> DELETE FROM tasks WHERE status = 'DONE' RETURNING *; -</programlisting> +</programlisting> </para> <para> @@ -259,7 +262,7 @@ DELETE FROM tasks WHERE status = 'DONE' RETURNING *; <literal>c_tasks</> is currently positioned: <programlisting> DELETE FROM tasks WHERE CURRENT OF c_tasks; -</programlisting> +</programlisting> </para> </refsect1> |