Add csvlog output for the new query_id value

This also adjusts the printf format for query id used by log_line_prefix
(%Q).

Reported-by: Justin Pryzby

Discussion: https://postgr.es/m/20210408005402.GG24239@momjian.us

Author: Julien Rouhaud, Bruce Momjian

doc/src/sgml/config.sgml

@@ -7310,7 +7310,8 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
         character count of the error position therein,
         location of the error in the PostgreSQL source code
         (if <varname>log_error_verbosity</varname> is set to <literal>verbose</literal>),
-        application name, backend type, and process ID of parallel group leader.
+        application name, backend type, process ID of parallel group leader,
+        and query id.
         Here is a sample table definition for storing CSV-format log output:
 
 <programlisting>
@@ -7341,6 +7342,7 @@ CREATE TABLE postgres_log
   application_name text,
   backend_type text,
   leader_pid integer,
+  query_id bigint,
   PRIMARY KEY (session_id, session_line_num)
 );
 </programlisting>

doc/src/sgml/file-fdw.sgml

@@ -266,7 +266,8 @@ CREATE FOREIGN TABLE pglog (
   location text,
   application_name text,
   backend_type text,
-  leader_pid integer
+  leader_pid integer,
+  query_id bigint
 ) SERVER pglog
 OPTIONS ( filename 'log/pglog.csv', format 'csv' );
 </programlisting>

src/backend/utils/error/elog.c

@@ -2716,11 +2716,11 @@ log_line_prefix(StringInfo buf, ErrorData *edata)
 				break;
 			case 'Q':
 				if (padding != 0)
-					appendStringInfo(buf, "%*ld", padding,
-							pgstat_get_my_queryid());
+					appendStringInfo(buf, "%*lld", padding,
+							(long long) pgstat_get_my_queryid());
 				else
-					appendStringInfo(buf, "%ld",
-							pgstat_get_my_queryid());
+					appendStringInfo(buf, "%lld",
+							(long long) pgstat_get_my_queryid());
 				break;
 			default:
 				/* format error - ignore it */
@@ -2964,6 +2964,10 @@ write_csvlog(ErrorData *edata)
 		if (leader && leader->pid != MyProcPid)
 			appendStringInfo(&buf, "%d", leader->pid);
 	}
+	appendStringInfoChar(&buf, ',');
+
+	/* query id */
+	appendStringInfo(&buf, "%lld", (long long) pgstat_get_my_queryid());
 
 	appendStringInfoChar(&buf, '\n');