Add note that inlined SQL functions aren't tracked by track_functions.

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 5cc395efa22e2825a388cee029cdd0da1cedcf5a..223911c7c682004a7c3a8d54c25d32962b49cf0a 100644 (file)
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -3361,11 +3361,19 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
       <listitem>
        <para>
         Enables tracking of function call counts and time used. Specify
-        <literal>pl</literal> to count only procedural language functions,
+        <literal>pl</literal> to track only procedural-language functions,
         <literal>all</literal> to also track SQL and C language functions.
-        The default is <literal>none</literal>.
-        Only superusers can change this setting.
+        The default is <literal>none</literal>, which disables function
+        statistics tracking.  Only superusers can change this setting.
        </para>
+
+       <note>
+        <para>
+         SQL-language functions that are simple enough to be <quote>inlined</>
+         into the calling query will not be tracked, regardless of this
+         setting.
+        </para>
+       </note>
       </listitem>
      </varlistentry>