Provide for logfiles in machine readable CSV format. In consequence, rename

redirect_stderr to logging_collector.
Original patch from Arul Shaji, subsequently modified by Greg Smith, and then
heavily modified by me.

Author: adunstan

doc/src/sgml/config.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.137 2007/08/13 19:27:11 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.138 2007/08/19 01:41:23 adunstan Exp $ -->
 
 <chapter Id="runtime-config">
   <title>Server Configuration</title>
@@ -2261,7 +2261,7 @@ SELECT * FROM parent WHERE key = 2400;
        <para>
         <productname>PostgreSQL</productname> supports several methods
          for logging server messages, including
-         <systemitem>stderr</systemitem> and
+         <systemitem>stderr</systemitem>, <systemitem>csvlog</systemitem> and
          <systemitem>syslog</systemitem>. On Windows, 
          <systemitem>eventlog</systemitem> is also supported. Set this
          parameter to a list of desired log destinations separated by
@@ -2270,24 +2270,33 @@ SELECT * FROM parent WHERE key = 2400;
          This parameter can only be set in the <filename>postgresql.conf</>
          file or on the server command line.
        </para>
+       <para> If <varname>log_destination</> is set to <systemitem>csvlog</systemitem>, 
+         the log is output as comma seperated values. The format is:
+         timestamp with milliseconds, username, database name, session id, host:port number,
+         process id, per process line number, command tag, session start time, transaction id, 
+         error severity, SQL state code, statement/error message. 
+       </para>
       </listitem>
      </varlistentry>
 
-     <varlistentry id="guc-redirect-stderr" xreflabel="redirect_stderr">
-      <term><varname>redirect_stderr</varname> (<type>boolean</type>)</term>
+     <varlistentry id="guc-logging-collector" xreflabel="logging_collector">
+      <term><varname>logging_collector</varname> (<type>boolean</type>)</term>
       <indexterm>
-       <primary><varname>redirect_stderr</> configuration parameter</primary>
+       <primary><varname>logging_collector</> configuration parameter</primary>
       </indexterm>
       <listitem>
        <para>
-         This parameter allows messages sent to <application>stderr</> to be
+         This parameter allows messages sent to <application>stderr</>,
+		 and CSV logs, to be
          captured and redirected into log files.
          This method, in combination with logging to <application>stderr</>,
          is often more useful than
          logging to <application>syslog</>, since some types of messages
          might not appear in <application>syslog</> output (a common example
          is dynamic-linker failure messages).
          This parameter can only be set at server start.
+		 <varname>start_log_collector</varname> must be enabled to generate 
+		 CSV logs.
        </para>
       </listitem>
      </varlistentry>
@@ -2299,8 +2308,8 @@ SELECT * FROM parent WHERE key = 2400;
       </indexterm>
       <listitem>
        <para>
-        When <varname>redirect_stderr</> is enabled, this parameter
-        determines the directory in which log files will be created.
+        When <varname>logging_collector</> is enabled, 
+        this parameter determines the directory in which log files will be created.
         It can be specified as an absolute path, or relative to the
         cluster data directory.
         This parameter can only be set in the <filename>postgresql.conf</>
@@ -2316,8 +2325,8 @@ SELECT * FROM parent WHERE key = 2400;
       </indexterm>
       <listitem>
        <para>
-        When <varname>redirect_stderr</varname> is enabled, this parameter
-        sets the file names of the created log files.  The value
+        When <varname>logging_collector</varname> is enabled,
+        this parameter sets the file names of the created log files.  The value
         is treated as a <systemitem>strftime</systemitem> pattern,
         so <literal>%</literal>-escapes can be used to specify time-varying
         file names.  (Note that if there are
@@ -2332,6 +2341,14 @@ SELECT * FROM parent WHERE key = 2400;
         This parameter can only be set in the <filename>postgresql.conf</>
         file or on the server command line.
        </para>
+       <para>
+	    If <varname>log_destination</> is set to <systemitem>csvlog</>,
+		<literal>.csv</> will be appended to the timestamped 
+		<varname>log_filename</> to create the final log file name. 
+		(If log_filename ends in <literal>.log</>, the suffix is overwritten.) 
+		In the case of the example above, the 
+        file name will be <literal>server_log.1093827753.csv</literal>
+       </para>
       </listitem>
      </varlistentry>
 
@@ -2342,8 +2359,8 @@ SELECT * FROM parent WHERE key = 2400;
       </indexterm>
       <listitem>
        <para>
-        When <varname>redirect_stderr</varname> is enabled, this parameter
-        determines the maximum lifetime of an individual log file.
+        When <varname>logging_collector</varname> is enabled,
+        this parameter determines the maximum lifetime of an individual log file.
         After this many minutes have elapsed, a new log file will
         be created.  Set to zero to disable time-based creation of
         new log files.
@@ -2360,8 +2377,8 @@ SELECT * FROM parent WHERE key = 2400;
       </indexterm>
       <listitem>
        <para>
-        When <varname>redirect_stderr</varname> is enabled, this parameter
-        determines the maximum size of an individual log file.
+        When <varname>logging_collector</varname> is enabled,
+        this parameter determines the maximum size of an individual log file.
         After this many kilobytes have been emitted into a log file,
         a new log file will be created.  Set to zero to disable size-based
         creation of new log files.
@@ -2378,8 +2395,8 @@ SELECT * FROM parent WHERE key = 2400;
       </indexterm>
       <listitem>
        <para>
-        When <varname>redirect_stderr</varname> is enabled, this parameter will cause
-        <productname>PostgreSQL</productname> to truncate (overwrite),
+        When <varname>logging_collector</varname> is enabled,
+        this parameter will cause <productname>PostgreSQL</productname> to truncate (overwrite),
         rather than append to, any existing log file of the same name.
         However, truncation will occur only when a new file is being opened
         due to time-based rotation, not during server startup or size-based
@@ -2599,7 +2616,7 @@ SELECT * FROM parent WHERE key = 2400;
         The server's standard output and standard error are redirected
         to <literal>/dev/null</>, so any messages sent to them will be lost.
         Unless <application>syslog</> logging is selected or
-        <varname>redirect_stderr</> is enabled, using this parameter
+        <varname>start_log_collector</> is enabled, using this parameter
         is discouraged because it makes it impossible to see error messages.
         This parameter can only be set at server start.
        </para>
@@ -3066,6 +3083,94 @@ SELECT * FROM parent WHERE key = 2400;
      </varlistentry>
 
      </variablelist>
+    </sect2>
+     <sect2 id="runtime-config-logging-csvlog">
+     <title>Using the csvlog</title>
+
+       <para>
+	    Including <literal>csvlog</> in the <varname>log_destination</> list 
+		provides a convenient way to import log files into a database table. 
+		Here is a sample table definition for storing csvlog output:
+       </para>
+
+<programlisting>
+CREATE TABLE postgres_log
+(
+  log_time timestamp,
+  username text,
+  database_name text,
+  sessionid text not null,
+  connection_from text,
+  process_id text,
+  process_line_num int not null,
+  command_tag text,
+  session_start_time timestamp,
+  transaction_id int,
+  error_severity text,
+  sql_state_code text,
+  statement text,
+  PRIMARY KEY (sessionid, process_line_num)
+);
+</programlisting>
+
+
+       <para>
+       In order to import into this table, use the COPY FROM command:
+       </para>
+
+<programlisting>
+COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
+</programlisting>
+
+       <para>
+       There are a few things you need to import csvlog files easily and 
+	   automatically:
+
+       <orderedlist>
+         <listitem>
+           <para>
+            Use a consistant, predictable naming scheme for your log files 
+            with <varname>log_filename</varname>.  This lets you predict what 
+the file name will be when it is ready to be imported.
+guess what 
+            the file name will be and know when an individual log file is 
+            complete and therefore ready to be imported.
+         </para>
+        </listitem>
+
+        <listitem>
+           <para>
+            Set <varname>log_rotation_size</varname> to 0 to disable 
+			size-based log rotation, as it makes the log filename difficult 
+			to predict. 
+           </para>
+        </listitem>
+
+        <listitem>
+          <para>
+           Set <varname>log_truncate_on_rotate</varname> = on so that old 
+		   log data isn't mixed with the new in the same file.
+          </para>
+        </listitem>
+
+        <listitem>
+          <para>
+           The example above includes a useful primary key on the log
+           file data, which will protect against accidentally importing
+           the same information twice.  The COPY command commits all of
+           the data it imports at one time, and any single error will
+           cause the entire import to fail.  
+		   If you import a partial log file and later import the file again 
+		   when it is complete, the primary key violation will cause the 
+		   import to fail. Wait until the log is complete and closed before 
+		   import. This will also protect against accidently importing a 
+		   partial line that hasn't been completely written, which would 
+		   also cause the COPY to fail.
+          </para>
+        </listitem>
+        </orderedlist>
+      </para>
+
     </sect2>
    </sect1>
 

doc/src/sgml/func.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.385 2007/08/13 01:18:47 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.386 2007/08/19 01:41:23 adunstan Exp $ -->
 
  <chapter id="functions">
   <title>Functions and Operators</title>
@@ -11254,9 +11254,9 @@ SELECT set_config('log_statement_stats', 'off', false);
 
    <para>
     <function>pg_rotate_logfile</> signals the log-file manager to switch
-    to a new output file immediately.  This works only when
-    <varname>redirect_stderr</> is used for logging, since otherwise there
-    is no log-file manager subprocess.
+    to a new output file immediately.  This works only when the built-in
+	log collector if running, since otherwise there is no log-file manager 
+	subprocess.
    </para>
 
    <indexterm zone="functions-admin">

doc/src/sgml/maintenance.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.77 2007/07/23 17:22:00 alvherre Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.78 2007/08/19 01:41:24 adunstan Exp $ -->
 
 <chapter id="maintenance">
  <title>Routine Database Maintenance Tasks</title>
@@ -691,10 +691,11 @@ analyze threshold = analyze base threshold + analyze scale factor * number of tu
    A better approach is to send the server's
    <systemitem>stderr</> output to some type of log rotation program.
    There is a built-in log rotation program, which you can use by
-   setting the configuration parameter <literal>redirect_stderr</> to
+   setting the configuration parameter <literal>logging_collector</> to
    <literal>true</> in <filename>postgresql.conf</>.  The control
    parameters for this program are described in <xref
-   linkend="runtime-config-logging-where">.
+   linkend="runtime-config-logging-where">. You can also use this approach
+   to capture the log data in machine readable CSV format.
   </para>
 
   <para>

src/backend/postmaster/postmaster.c

@@ -37,7 +37,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.540 2007/08/09 01:18:43 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.541 2007/08/19 01:41:24 adunstan Exp $
  *
  * NOTES
  *
@@ -1282,8 +1282,8 @@ ServerLoop(void)
 			}
 		}
 
-		/* If we have lost the system logger, try to start a new one */
-		if (SysLoggerPID == 0 && Redirect_stderr)
+		/* If we have lost the log collector, try to start a new one */
+		if (SysLoggerPID == 0 && Logging_collector)
 			SysLoggerPID = SysLogger_Start();
 
 		/*