Various pgbench enhancements. Patch contributed by ITAGAKI Takahiro.

Also tweak README.pgbench/README.pgbench_jis:
  Remove history after pgbench was added to PostgreSQL contrib module.
  Those info was not only redundant since it has already been in CVS
  log, but also incomplete.
--------------------------------------------------------------------------
The attached is a patch to optimize contrib/pgbench using new 8.3 features.

- Use DROP IF EXISTS to suppress errors for initial loadings.
- Use a combination of TRUNCATE and COPY to reduce WAL on creating
  the accounts table.

Also, there are some cosmetic changes.

- Change the output of -v option from "starting full vacuum..."
  to "starting vacuum accounts..." in reflection of the fact.
- Shape duplicated error checks into executeStatement().


There is a big performance win in "COPY with no WAL" feature.
Thanks for the efforts!
--------------------------------------------------------------------------

contrib/pgbench/README.pgbench

-pgbench README		2006/10/21 Tatsuo Ishii
+$PostgreSQL: pgsql/contrib/pgbench/README.pgbench,v 1.16 2007/04/06 08:49:44 ishii Exp $
+
+pgbench README
 
 o What is pgbench?
 
@@ -233,54 +235,7 @@ o License?
 
 Basically it is same as BSD license. See pgbench.c for more details.
 
-o History
-
-2006/10/21
-	* more fix with handling default scaling factor in the default
-          scenarios
-
-2006/09/14
-	* change "tps" to "scale" to avoid confusion
-
-	* fix bug with handling default scaling factor in the default
-          scenarios
-
-2006/07/26
-	* New features contributed by Tomoaki Sato.
-
-	* predefined variable "tps"
-	    The value of variable tps is taken from the scaling factor
-	    specified by -s option.
-        * -D option
-	   Variable values can be defined by -D option.
-	* \set command now allows arithmetic calculations.
-
-2005/09/29
-	* add -f option. contributed by Tomoaki Sato.
-
-[updation records were missing]
-
-2003/11/26
-	* create indexes after data insertion to reduce time.
-	  patch from Yutaka Tanida.
-
-2003/06/10
-	* fix uninitialized memory bug
-	* add support for PGHOST, PGPORT, PGUSER environment variables
-
-2002/07/20
-	* patch contributed by Neil Conway.
-	* code/document clean up and add -l option.
-
-2002/02/24
-	* do not CHECKPOINT anymore while initializing benchmark
-	* database. Add -N option.
-
-2001/10/24
-	* "time"->"mtime"
-
-2001/09/09
-	* Add -U, -P, -C options
+o History before contributed to PostgreSQL
 
 2000/1/15 pgbench-1.2 contributed to PostgreSQL
 	* Add -v option

contrib/pgbench/README.pgbench_jis

-pgbench README		2006/10/21 Tatsuo Ishii
+$PostgreSQL: pgsql/contrib/pgbench/README.pgbench_jis,v 1.17 2007/04/06 08:49:44 ishii Exp $
+
+pgbench README
 
 $B"#(Bpgbench $B$H$O!)(B
 
@@ -283,57 +285,7 @@ pgbench $B$O@P0f(B $BC#IW$K$h$C$F=q$+$l$^$7$?!%%i%$%;%s%9>r7o$O(B pgbench.c
 $BKAF,$K=q$$$F$"$j$^$9!%$3$N>r7o$r<i$k8B$jL5=~$GMxMQ$7!$$^$?<+M3$K:FG[IU(B
 $B$G$-$^$9!%(B
 
-$B"#2~DjMzNr(B
-
-2006/10/21
-	* $B99$K%G%U%)%k%H$N%9%1!<%j%s%0%U%!%/%?$r(Bbranches$B$+$i<h$C$F$3$J(B
-          $B$$%P%0$r=$@5!%(B
-
-2006/09/13
-	* $BJQ?t(Btps$B$OJ6$i$o$7$$$N$G(Bscale$B$KJQ99!%%G%U%)%k%H%7%J%j%*$N;~$K!$(B
-	  $B%G%U%)%k%H$N%9%1!<%j%s%0%U%!%/%?$r(Bbranches$B$+$i<h$C$F$3$J$$%P%0$r=$@5!%(B
-
-2006/07/26
-	* $B:4F#$5$s$N%Q%C%A$rE,MQ!%0J2<$N5!G=DI2C!%(BPostgreSQL 8.2$B$K<h$j(B
-	$B9~$^$l$^$9!%(B
-
-	$BJQ?t(B tps
-	    -s $B%*%W%7%g%s$G;XDj$7$?%9%1!<%j%s%0%U%!%/%?!<$r%U%!%$%kFb$GJQ?t$H$7(B
-	   $B$F;2>H$9$k5!G=(B
-        -D $B%*%W%7%g%s(B
-	   $B%3%^%s%I$N%*%W%7%g%s$H$7$FDj5A$7$?JQ?t$r%U%!%$%kFb$+$i;2>H$9$k5!G=(B
-	\set $B%3%^%s%I(B
-	   $B%U%!%$%kFb$G;MB'1i;;$r9T$$!"$=$N7k2L$rJQ?t$KBeF~$9$k5!G=(B
-
-2005/09/29
-	* $B:4F#$5$s$N%Q%C%A$rE,MQ!%(B-f $B%*%W%7%g%s$NDI2C!%(B
-
-[$B$3$N4V$$$m$$$mJQ99$,$"$C$?$h$&$@$,(BREADME$B$O%a%$%s%F%J%s%9$5$l$F$$$J$$(B]
-
-2003/11/26
-	* $BC+ED$5$s$N%Q%C%A$rE,MQ!%(Bpgbench -i$B$N:]$K!$8e$+$i<g%-!<$r:n@.(B
-	  $B$9$k$h$&$K$7$?!%$3$l$K$h$C$F=i4|2=$N<B9T;~4V$,BgI}$KC;=L$G$-(B
-	  $B$k(B($B$O$:(B)$B!%(B
-
-2003/06/10
-	* $B%a%b%j$,=i4|2=$5$l$F$$$J$$%P%0$r=$@5(B
-	* $B4D6-JQ?t(BPGHOST, PGPORT, PGUSER$B$rG'<1$9$k$h$&$K$7$?!%(B
-
-2002/07/20
-	* Nei Conway$B$5$s$N%Q%C%A$rE,MQ!%(B
-	* -l $B%*%W%7%g%s$NDI2C!%(B
-
-2002/02/24
-	* $B$3$3$+$i$O(B7.3$BMQ$NJQ99$G$9!%(B
-	* CHECKPOINT$B$NH/9T$r$d$a$^$7$?!%(B
-	* -N $B%*%W%7%g%s$rDI2C$7$^$7$?!%(B
-
-2001/10/24
-	* PostgreSQL 7.2$B$G!$(B"time"$B$,M=Ls8l$K$J$C$?$N$G!$(B"mtime"$B$KJQ99(B
-	$B$7$?!%(B
-
-2001/09/09
-	* PostgreSQL 7.2$BMQ$K!$(B-U, -P, -C $B%*%W%7%g%s$rDI2C$7$^$7$?!%(B
+$B"#(BPostgreSQL$B$N(Bcontrib$B%b%8%e!<%k$H$7$F<h$j9~$^$l$k$^$G$N2~DjMzNr(B
 
 2000/1/15 pgbench-1.2 $B$O(B PostgreSQL $B$K(B contribute $B$5$l$^$7$?!%(B
 	* -v $B%*%W%7%g%sDI2C(B

contrib/pgbench/pgbench.c

 /*
- * $PostgreSQL: pgsql/contrib/pgbench/pgbench.c,v 1.62 2007/03/13 09:06:35 mha Exp $
+ * $PostgreSQL: pgsql/contrib/pgbench/pgbench.c,v 1.63 2007/04/06 08:49:44 ishii Exp $
  *
  * pgbench: a simple benchmark program for PostgreSQL
  * written by Tatsuo Ishii
@@ -188,12 +188,26 @@ getrand(int min, int max)
 	return min + (int) (((max - min) * (double) random()) / MAX_RANDOM_VALUE + 0.5);
 }
 
+/* call PQexec() and exit() on failure */
+static void
+executeStatement(PGconn *con, const char* sql)
+{
+	PGresult   *res;
+
+	res = PQexec(con, sql);
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "%s", PQerrorMessage(con));
+		exit(1);
+	}
+	PQclear(res);
+}
+
 /* set up a connection to the backend */
 static PGconn *
 doConnect(void)
 {
 	PGconn	   *con;
-	PGresult   *res;
 
 	con = PQsetdbLogin(pghost, pgport, pgoptions, pgtty, dbName,
 					   login, pwd);
@@ -216,13 +230,7 @@ doConnect(void)
 		return (NULL);
 	}
 
-	res = PQexec(con, "SET search_path = public");
-	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-	{
-		fprintf(stderr, "%s", PQerrorMessage(con));
-		exit(1);
-	}
-	PQclear(res);
+	executeStatement(con, "SET search_path = public");
 
 	return (con);
 }
@@ -720,18 +728,18 @@ init(void)
 	PGconn	   *con;
 	PGresult   *res;
 	static char *DDLs[] = {
-		"drop table branches",
+		"drop table if exists branches",
 		"create table branches(bid int not null,bbalance int,filler char(88))",
-		"drop table tellers",
+		"drop table if exists tellers",
 		"create table tellers(tid int not null,bid int,tbalance int,filler char(84))",
-		"drop table accounts",
+		"drop table if exists accounts",
 		"create table accounts(aid int not null,bid int,abalance int,filler char(84))",
-		"drop table history",
-	"create table history(tid int,bid int,aid int,delta int,mtime timestamp,filler char(22))"};
+		"drop table if exists history",
+		"create table history(tid int,bid int,aid int,delta int,mtime timestamp,filler char(22))"};
 	static char *DDLAFTERs[] = {
 		"alter table branches add primary key (bid)",
 		"alter table tellers add primary key (tid)",
-	"alter table accounts add primary key (aid)"};
+		"alter table accounts add primary key (aid)"};
 
 
 	char		sql[256];
@@ -741,77 +749,46 @@ init(void)
 	if ((con = doConnect()) == NULL)
 		exit(1);
 
-	for (i = 0; i < (sizeof(DDLs) / sizeof(char *)); i++)
-	{
-		res = PQexec(con, DDLs[i]);
-		if (strncmp(DDLs[i], "drop", 4) && PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
-	}
+	for (i = 0; i < lengthof(DDLs); i++)
+		executeStatement(con, DDLs[i]);
 
-	res = PQexec(con, "begin");
-	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-	{
-		fprintf(stderr, "%s", PQerrorMessage(con));
-		exit(1);
-	}
-	PQclear(res);
+	executeStatement(con, "begin");
 
 	for (i = 0; i < nbranches * scale; i++)
 	{
 		snprintf(sql, 256, "insert into branches(bid,bbalance) values(%d,0)", i + 1);
-		res = PQexec(con, sql);
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
+		executeStatement(con, sql);
 	}
 
 	for (i = 0; i < ntellers * scale; i++)
 	{
 		snprintf(sql, 256, "insert into tellers(tid,bid,tbalance) values (%d,%d,0)"
 				 ,i + 1, i / ntellers + 1);
-		res = PQexec(con, sql);
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
+		executeStatement(con, sql);
 	}
 
-	res = PQexec(con, "end");
-	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	executeStatement(con, "commit");
+
+	/*
+	 * fill the accounts table with some data
+	 */
+	fprintf(stderr, "creating tables...\n");
+
+	executeStatement(con, "begin");
+	executeStatement(con, "truncate accounts");
+
+	res = PQexec(con, "copy accounts from stdin");
+	if (PQresultStatus(res) != PGRES_COPY_IN)
 	{
 		fprintf(stderr, "%s", PQerrorMessage(con));
 		exit(1);
 	}
 	PQclear(res);
 
-	/*
-	 * occupy accounts table with some data
-	 */
-	fprintf(stderr, "creating tables...\n");
 	for (i = 0; i < naccounts * scale; i++)
 	{
 		int			j = i + 1;
 
-		if (j % 10000 == 1)
-		{
-			res = PQexec(con, "copy accounts from stdin");
-			if (PQresultStatus(res) != PGRES_COPY_IN)
-			{
-				fprintf(stderr, "%s", PQerrorMessage(con));
-				exit(1);
-			}
-			PQclear(res);
-		}
-
 		snprintf(sql, 256, "%d\t%d\t%d\t\n", j, i / naccounts + 1, 0);
 		if (PQputline(con, sql))
 		{
@@ -820,62 +797,32 @@ init(void)
 		}
 
 		if (j % 10000 == 0)
-		{
-			/*
-			 * every 10000 tuples, we commit the copy command. this should
-			 * avoid generating too much WAL logs
-			 */
 			fprintf(stderr, "%d tuples done.\n", j);
-			if (PQputline(con, "\\.\n"))
-			{
-				fprintf(stderr, "very last PQputline failed\n");
-				exit(1);
-			}
-
-			if (PQendcopy(con))
-			{
-				fprintf(stderr, "PQendcopy failed\n");
-				exit(1);
-			}
-
-#ifdef NOT_USED
-
-			/*
-			 * do a checkpoint to purge the old WAL logs
-			 */
-			res = PQexec(con, "checkpoint");
-			if (PQresultStatus(res) != PGRES_COMMAND_OK)
-			{
-				fprintf(stderr, "%s", PQerrorMessage(con));
-				exit(1);
-			}
-			PQclear(res);
-#endif   /* NOT_USED */
-		}
 	}
-	fprintf(stderr, "set primary key...\n");
-	for (i = 0; i < (sizeof(DDLAFTERs) / sizeof(char *)); i++)
+	if (PQputline(con, "\\.\n"))
 	{
-		res = PQexec(con, DDLAFTERs[i]);
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
+		fprintf(stderr, "very last PQputline failed\n");
+		exit(1);
 	}
-
-	/* vacuum */
-	fprintf(stderr, "vacuum...");
-	res = PQexec(con, "vacuum analyze");
-	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	if (PQendcopy(con))
 	{
-		fprintf(stderr, "%s", PQerrorMessage(con));
+		fprintf(stderr, "PQendcopy failed\n");
 		exit(1);
 	}
-	PQclear(res);
-	fprintf(stderr, "done.\n");
+	executeStatement(con, "commit");
+
+	/*
+	 * create indexes
+	 */
+	fprintf(stderr, "set primary key...\n");
+	for (i = 0; i < lengthof(DDLAFTERs); i++)
+		executeStatement(con, DDLAFTERs[i]);
 
+	/* vacuum */
+	fprintf(stderr, "vacuum...");
+	executeStatement(con, "vacuum analyze");
+
+	fprintf(stderr, "done.\n");
 	PQfinish(con);
 }
 
@@ -1155,7 +1102,7 @@ main(int argc, char **argv)
 	int			c;
 	int			is_init_mode = 0;		/* initialize mode? */
 	int			is_no_vacuum = 0;		/* no vacuum at all before testing? */
-	int			is_full_vacuum = 0;		/* do full vacuum before testing? */
+	int			do_vacuum_accounts = 0;	/* do vacuum accounts before testing? */
 	int			debug = 0;		/* debug flag */
 	int			ttype = 0;		/* transaction type. 0: TPC-B, 1: SELECT only,
 								 * 2: skip update of branches and tellers */
@@ -1219,7 +1166,7 @@ main(int argc, char **argv)
 				is_no_vacuum++;
 				break;
 			case 'v':
-				is_full_vacuum++;
+				do_vacuum_accounts++;
 				break;
 			case 'p':
 				pgport = optarg;
@@ -1456,49 +1403,16 @@ main(int argc, char **argv)
 	if (!is_no_vacuum)
 	{
 		fprintf(stderr, "starting vacuum...");
-		res = PQexec(con, "vacuum branches");
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
-
-		res = PQexec(con, "vacuum tellers");
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
-
-		res = PQexec(con, "delete from history");
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
-		res = PQexec(con, "vacuum history");
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			fprintf(stderr, "%s", PQerrorMessage(con));
-			exit(1);
-		}
-		PQclear(res);
-
+		executeStatement(con, "vacuum branches");
+		executeStatement(con, "vacuum tellers");
+		executeStatement(con, "delete from history");
+		executeStatement(con, "vacuum history");
 		fprintf(stderr, "end.\n");
 
-		if (is_full_vacuum)
+		if (do_vacuum_accounts)
 		{
-			fprintf(stderr, "starting full vacuum...");
-			res = PQexec(con, "vacuum analyze accounts");
-			if (PQresultStatus(res) != PGRES_COMMAND_OK)
-			{
-				fprintf(stderr, "%s", PQerrorMessage(con));
-				exit(1);
-			}
-			PQclear(res);
+			fprintf(stderr, "starting vacuum accounts...");
+			executeStatement(con, "vacuum analyze accounts");
 			fprintf(stderr, "end.\n");
 		}
 	}