Default stats_command_string to 'on', now that its overhead is minimal.

doc/src/sgml/config.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.66 2006/06/19 01:51:21 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.67 2006/06/27 19:07:50 momjian Exp $ -->
 
 <chapter Id="runtime-config">
   <title>Server Configuration</title>
@@ -2878,7 +2878,7 @@ SELECT * FROM parent WHERE key = 2400;
        <para>
         Enables the collection of information on the currently
         executing command of each session, along with the time at
-        which that command began execution. This parameter is off by
+        which that command began execution. This parameter is on by
         default. Note that even when enabled, this information is not
         visible to all users, only to superusers and the user owning
         the session being reported on; so it should not represent a

doc/src/sgml/monitoring.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.34 2006/06/19 01:51:21 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.35 2006/06/27 19:07:50 momjian Exp $ -->
 
 <chapter id="monitoring">
  <title>Monitoring Database Activity</title>
@@ -170,12 +170,11 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
 
    <note>
     <para>
-     Since the parameters <varname>stats_command_string</varname>,
-     <varname>stats_block_level</varname>, and
+     Since the parameters <varname>stats_block_level</varname>, and
      <varname>stats_row_level</varname> default to <literal>false</>,
      very few statistics are collected in the default
-     configuration. Enabling one or more of these configuration
-     variables will significantly enhance the amount of useful data
+     configuration. Enabling either of these configuration
+     variables will significantly increase the amount of useful data
      produced by the statistics facilities, at the expense of
      additional run-time overhead.
     </para>
@@ -241,9 +240,9 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
       process <acronym>ID</>, user OID, user name, current query, time at
       which the current query began execution, time at which the process
       was started, and client's address and port number.  The columns
-      that report data on the current query are only available if the
+      that report data on the current query are available unless the
       parameter <varname>stats_command_string</varname> has been
-      turned on.  Furthermore, these columns read as null unless the
+      turned off.  Furthermore, these columns are only visible if the
       user examining the view is a superuser or the same as the user
       owning the process being reported on.
      </entry>
@@ -635,10 +634,10 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
       <entry><literal><function>pg_stat_get_backend_activity</function>(<type>integer</type>)</literal></entry>
       <entry><type>text</type></entry>
       <entry>
-       Active command of the given server process (null if the
-       current user is not a superuser nor the same user as that of
-       the session being queried, or
-       <varname>stats_command_string</varname> is not on)
+       Active command of the given server process, but only if the
+       current user is a superuser or the same user as that of
+       the session being queried (and
+       <varname>stats_command_string</varname> is on)
       </entry>
      </row>
 
@@ -647,10 +646,10 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
       <entry><type>timestamp with time zone</type></entry>
       <entry>
        The time at which the given server process' currently
-       executing query was started (null if the
-       current user is not a superuser nor the same user as that of
-       the session being queried, or
-       <varname>stats_command_string</varname> is not on)
+       executing query was started, but only if the
+       current user is a superuser or the same user as that of
+       the session being queried (and
+       <varname>stats_command_string</varname> is on)
       </entry>
      </row>
 

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.322 2006/06/19 01:51:21 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.323 2006/06/27 19:07:50 momjian Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -725,7 +725,7 @@ static struct config_bool ConfigureNamesBool[] =
 						 "at which that command began execution.")
 		},
 		&pgstat_collect_querystring,
-		false, NULL, NULL
+		true, NULL, NULL
 	},
 
 	{

src/backend/utils/misc/postgresql.conf.sample

@@ -322,7 +322,7 @@
 
 # - Query/Index Statistics Collector -
 
-#stats_command_string = off
+#stats_command_string = on
 #stats_start_collector = on		# needed for block or row stats
 #stats_block_level = off
 #stats_row_level = off