aboutsummaryrefslogtreecommitdiff
path: root/doc/src
diff options
context:
space:
mode:
authorTom Lane <tgl@sss.pgh.pa.us>2001-04-30 22:22:34 +0000
committerTom Lane <tgl@sss.pgh.pa.us>2001-04-30 22:22:34 +0000
commitc8b5598a116d2d6079f941bcfce7a052f573f5bc (patch)
tree340ac667f4a4f68ca1413d7ecb0ef2896b771906 /doc/src
parent955c8771f865c6601f99d9acb6d525a23b637ba2 (diff)
downloadpostgresql-c8b5598a116d2d6079f941bcfce7a052f573f5bc.tar.gz
postgresql-c8b5598a116d2d6079f941bcfce7a052f573f5bc.zip
Document pltcl's return_null command.
Diffstat (limited to 'doc/src')
-rw-r--r--doc/src/sgml/pltcl.sgml13
1 files changed, 10 insertions, 3 deletions
diff --git a/doc/src/sgml/pltcl.sgml b/doc/src/sgml/pltcl.sgml
index 59f464aebaf..7d7ceb33792 100644
--- a/doc/src/sgml/pltcl.sgml
+++ b/doc/src/sgml/pltcl.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.8 2001/03/25 10:16:12 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.9 2001/04/30 22:22:34 tgl Exp $
-->
<chapter id="pltcl">
@@ -96,8 +96,10 @@ CREATE FUNCTION <replaceable>funcname</replaceable> (<replaceable>argument-types
</programlisting>
When the function is called, the arguments are given as
- variables $1 ... $n to the Tcl procedure body. For example,
- a function
+ variables <literal>$1</literal> ... <literal>$n</literal> to the
+ Tcl procedure body. The result is returned
+ from the Tcl code in the usual way, with a <literal>return</literal>
+ statement. For example, a function
returning the higher of two int4 values could be defined as:
<programlisting>
@@ -107,6 +109,11 @@ CREATE FUNCTION tcl_max (int4, int4) RETURNS int4 AS '
' LANGUAGE 'pltcl';
</programlisting>
+ To return a NULL value from a PL/Tcl function, execute
+ <literal>return_null</literal>.
+ </para>
+
+ <para>
Composite type arguments are given to the procedure as Tcl arrays.
The element names
in the array are the attribute names of the composite