Enhance documentation about TopoElement domain

git-svn-id: http://svn.osgeo.org/postgis/trunk@10437 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/extras_topology.xml b/doc/extras_topology.xml
index 5ec2bad95385c8c19c765ce115540a6a6f1f9be7..53fb2e92534df0a9d0e34cce689a0a7017474224 100644 (file)
--- a/doc/extras_topology.xml
+++ b/doc/extras_topology.xml
@@ -136,10 +136,17 @@
                  </refnamediv>
                  <refsection>
                        <title>Description</title>
-                       <para>An array of 2 integers used to represent the id and type of a topology primitive or the id and layer of a TopoGeometry. Sets of such pairs are used to define TopoGeometry objects (either simple or hierarchical).</para>
+                       <para>An array of 2 integers used to represent the id (first element) and type (second element) of a topology primitive or the id (first element) and layer (second element) of a TopoGeometry. Sets of such pairs are used to define TopoGeometry objects (either simple or hierarchical).</para>
                  </refsection>
             <refsection>
                 <title>Examples</title>
+                 <programlisting>
+SELECT te[1] AS id, te[2] AS type FROM
+( SELECT ARRAY[1,2]::topology.topoelement AS te ) f;
+ id | type
+----+------
+  1 |    2
+                 </programlisting>
                  <programlisting>SELECT ARRAY[1,2]::topology.topoelement;
   te
 -------