Remove tabs from SGML file.

doc/src/sgml/func.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.453 2008/11/03 20:17:20 adunstan Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.454 2008/11/04 00:59:45 momjian Exp $ -->
 
  <chapter id="functions">
   <title>Functions and Operators</title>
@@ -12855,46 +12855,46 @@ SELECT (pg_stat_file('filename')).modification;
 
    <para>
       Currently <productname>PostgreSQL</> provides one built in trigger
-	  function, <function>suppress_redundant_updates_trigger</>, 
-	  which will prevent any update
-	  that does not actually change the data in the row from taking place, in
-	  contrast to the normal behaviour which always performs the update
-	  regardless of whether or not the data has changed. (This normal behaviour
-	  makes updates run faster, since no checking is required, and is also
-	  useful in certain cases.)
+      function, <function>suppress_redundant_updates_trigger</>, 
+      which will prevent any update
+      that does not actually change the data in the row from taking place, in
+      contrast to the normal behaviour which always performs the update
+      regardless of whether or not the data has changed. (This normal behaviour
+      makes updates run faster, since no checking is required, and is also
+      useful in certain cases.)
     </para>
 
-	<para>
-	  Ideally, you should normally avoid running updates that don't actually
-	  change the data in the record. Redundant updates can cost considerable
-	  unnecessary time, especially if there are lots of indexes to alter,
-	  and space in dead rows that will eventually have to be vacuumed.
-	  However, detecting such situations in client code is not
-	  always easy, or even possible, and writing expressions to detect
-	  them can be error-prone. An alternative is to use 
-	  <function>suppress_redundant_updates_trigger</>, which will skip
-	  updates that don't change the data. You should use this with care,
-	  however. The trigger takes a small but non-trivial time for each record, 
-	  so if most of the records affected by an update are actually changed,
-	  use of this trigger will actually make the update run slower.
+    <para>
+      Ideally, you should normally avoid running updates that don't actually
+      change the data in the record. Redundant updates can cost considerable
+      unnecessary time, especially if there are lots of indexes to alter,
+      and space in dead rows that will eventually have to be vacuumed.
+      However, detecting such situations in client code is not
+      always easy, or even possible, and writing expressions to detect
+      them can be error-prone. An alternative is to use 
+      <function>suppress_redundant_updates_trigger</>, which will skip
+      updates that don't change the data. You should use this with care,
+      however. The trigger takes a small but non-trivial time for each record, 
+      so if most of the records affected by an update are actually changed,
+      use of this trigger will actually make the update run slower.
     </para>
 
     <para>
       The <function>suppress_redundant_updates_trigger</> function can be 
-	  added to a table like this:
+      added to a table like this:
 <programlisting>
 CREATE TRIGGER z_min_update 
 BEFORE UPDATE ON tablename
 FOR EACH ROW EXECUTE PROCEDURE suppress_redundant_updates_trigger();
 </programlisting>
       In most cases, you would want to fire this trigger last for each row.
-	  Bearing in mind that triggers fire in name order, you would then
-	  choose a trigger name that comes after the name of any other trigger
+      Bearing in mind that triggers fire in name order, you would then
+      choose a trigger name that comes after the name of any other trigger
       you might have on the table.
     </para>
-	<para>
+    <para>
        For more information about creating triggers, see
-	    <xref linkend="SQL-CREATETRIGGER">.
+        <xref linkend="SQL-CREATETRIGGER">.
     </para>
   </sect1>
 </chapter>