diff --git a/doc/src/sgml/ref/pgbench.sgml b/doc/src/sgml/ref/pgbench.sgml
index 21182a7..ea0aa40 100644
--- a/doc/src/sgml/ref/pgbench.sgml
+++ b/doc/src/sgml/ref/pgbench.sgml
@@ -262,11 +262,13 @@ pgbench <optional> <replaceable>options</> </optional> <replaceable>dbname</>
 
     <variablelist>
      <varlistentry>
-      <term><option>-b</> <replaceable>scriptname</></term>
-      <term><option>--builtin</> <replaceable>scriptname</></term>
+      <term><option>-b</> <replaceable>scriptname[@weight]</></term>
+      <term><option>--builtin</> <replaceable>scriptname[@weight]</></term>
       <listitem>
        <para>
         Add the specified builtin script to the list of executed scripts.
+        An optional integer weight after <literal>@</> allows to adjust the
+        probability of drawing the test.
         Available builtin scripts are: <literal>tpcb-like</>,
         <literal>simple-update</> and <literal>select-only</>.
         The provided <replaceable>scriptname</> needs only to be a prefix
@@ -324,12 +326,14 @@ pgbench <optional> <replaceable>options</> </optional> <replaceable>dbname</>
      </varlistentry>
 
      <varlistentry>
-      <term><option>-f</> <replaceable>filename</></term>
-      <term><option>--file=</><replaceable>filename</></term>
+      <term><option>-f</> <replaceable>filename[@weight]</></term>
+      <term><option>--file=</><replaceable>filename[@weight]</></term>
       <listitem>
        <para>
         Add a transaction script read from <replaceable>filename</> to
         the list of executed scripts.
+        An optional integer weight after <literal>@</> allows to adjust the
+        probability of drawing the test.
         See below for details.
        </para>
       </listitem>
@@ -421,7 +425,7 @@ pgbench <optional> <replaceable>options</> </optional> <replaceable>dbname</>
       <listitem>
        <para>
         Run builtin simple-update script.
-        Shorthand for <option>-b simple-update</>.
+        Shorthand for <option>-b simple-update@1</>.
        </para>
       </listitem>
      </varlistentry>
@@ -539,7 +543,7 @@ pgbench <optional> <replaceable>options</> </optional> <replaceable>dbname</>
       <listitem>
        <para>
         Run built-in select-only script.
-        Shorthand for <option>-b select-only</>.
+        Shorthand for <option>-b select-only@1</>.
        </para>
       </listitem>
      </varlistentry>
@@ -692,6 +696,9 @@ pgbench <optional> <replaceable>options</> </optional> <replaceable>dbname</>
    Pgbench executes test scripts chosen randomly from a specified list.
    They include built-in scripts with <option>-b</> and
    user-provided custom scripts with <option>-f</>.
+   Each script may be given a relative weight specified after a
+   <literal>@</> so as to change its drawing probability.
+   The default weight is <literal>1</>.
  </para>
 
   <para>
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index b75cd80..cd2c0f3 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -179,6 +179,8 @@ char	   *login = NULL;
 char	   *dbName;
 const char *progname;
 
+#define WSEP '@' /* weight separator */
+
 volatile bool timer_exceeded = false;	/* flag from signal handler */
 
 /* variable definitions */
@@ -301,6 +303,7 @@ typedef struct
 typedef struct
 {
 	const char *name;
+	int weight;
 	Command **commands;
 	StatsData stats;
 } SQLScript;
@@ -308,6 +311,7 @@ typedef struct
 static SQLScript sql_script[MAX_SCRIPTS];
 static int	num_scripts;		/* number of script in sql_script[] */
 static int	num_commands = 0;	/* total number of Command structs */
+static int  total_weight = 0;
 
 static int	debug = 0;			/* debug flag */
 
@@ -404,13 +408,13 @@ usage(void)
 	 "  --tablespace=TABLESPACE  create tables in the specified tablespace\n"
 		   "  --unlogged-tables        create tables as unlogged tables\n"
 		   "\nBenchmarking options:\n"
-		   "  -b, --builtin=NAME       add buitin script among \"tpcb-like\"\n"
+		   "  -b, --builtin=NAME@W     add weighted buitin script among \"tpcb-like\"\n"
 		   "                           \"simple-update\" and \"select-only\".\n"
 		   "  -c, --client=NUM         number of concurrent database clients (default: 1)\n"
 		   "  -C, --connect            establish new connection for each transaction\n"
 		   "  -D, --define=VARNAME=VALUE\n"
 	  "                           define variable for use by custom script\n"
-		 "  -f, --file=FILENAME      add transaction script from FILENAME\n"
+		 "  -f, --file=FILENAME@W    add weighted transaction script from FILENAME\n"
 		   "  -j, --jobs=NUM           number of threads (default: 1)\n"
 		   "  -l, --log                write transaction times to log file\n"
 	"  -L, --latency-limit=NUM  count transactions lasting more than NUM ms as late\n"
@@ -1187,7 +1191,13 @@ clientDone(CState *st, bool ok)
 static int
 chooseScript(TState *thread)
 {
-	return getrand(thread, 0, num_scripts - 1);
+	int i = 0, w = 0, wc = (int) getrand(thread, 0, total_weight - 1);
+
+	do {
+		w += sql_script[i++].weight;
+	} while (w <= wc);
+
+	return i - 1;
 }
 
 /* return false iff client should be disconnected */
@@ -2616,8 +2626,41 @@ process_builtin(const char *tb, const char *source)
 	return my_commands;
 }
 
+/* Possiby truncate option and return weight */
+static int
+getWeight(char *option)
+{
+	char   *sep;
+	int		weight;
+
+	if ((sep = strrchr(option, WSEP)))
+	{
+		char *s;
+		*sep++ = '\0';
+
+		/* check that the weight is a positive integer */
+		s = sep;
+		while ('0' <= *s && *s <= '9')
+			s++;
+		if (*s != '\0' || s == sep)
+		{
+			/* empty or any other char */
+			fprintf(stderr,
+					"weight for script \"%s\" must be an integer, got \"%s\"\n",
+					option, sep);
+			exit(1);
+		}
+
+		weight = atoi(sep);
+	}
+	else
+		weight = 1;
+
+	return weight;
+}
+
 static void
-addScript(const char *name, Command ** commands)
+addScript(const char *name, Command ** commands, int weight)
 {
 	if (commands == NULL)
 	{
@@ -2632,6 +2675,7 @@ addScript(const char *name, Command ** commands)
 	}
 
 	sql_script[num_scripts].name = name;
+	sql_script[num_scripts].weight = weight;
 	sql_script[num_scripts].commands = commands;
 	initStats(& sql_script[num_scripts].stats, 0.0);
 	num_scripts++;
@@ -2721,9 +2765,9 @@ printResults(TState *threads, StatsData *total, instr_time total_time,
 
 		for (i = 0; i < num_scripts; i++)
 		{
-			printf("SQL script %d: %s\n"
+			printf("SQL script %d, weight %d: %s\n"
 				   " - "INT64_FORMAT" transactions (%.1f%% of total, tps = %f)\n",
-				   i+1, sql_script[i].name,
+				   i+1, sql_script[i].weight, sql_script[i].name,
 				   sql_script[i].stats.cnt,
 				   100.0 * sql_script[i].stats.cnt / total->cnt,
 				   sql_script[i].stats.cnt / time_include);
@@ -2814,6 +2858,7 @@ main(int argc, char **argv)
 	instr_time	conn_total_time;
 	int64		latency_late = 0;
 	StatsData	stats;
+	int			weight;
 	char	   *desc;
 
 	int			i;
@@ -2998,25 +3043,27 @@ main(int argc, char **argv)
 					exit(0);
 				}
 
+				weight = getWeight(optarg);
 				addScript(desc, process_builtin(
-							  find_builtin(optarg, &desc), desc));
+							  find_builtin(optarg, &desc), desc), weight);
 				benchmarking_option_set = true;
 				internal_script_used = true;
 				break;
 			case 'S':
 				addScript(desc, process_builtin(
-							  find_builtin("select-only", &desc), desc));
+							  find_builtin("select-only", &desc), desc), 1);
 				benchmarking_option_set = true;
 				internal_script_used = true;
 				break;
 			case 'N':
 				addScript(desc, process_builtin(
-							  find_builtin("simple-update", &desc), desc));
+							  find_builtin("simple-update", &desc), desc), 1);
 				benchmarking_option_set = true;
 				internal_script_used = true;
 				break;
 			case 'f':
-				addScript(optarg, process_file(optarg));
+				weight = getWeight(optarg);
+				addScript(optarg, process_file(optarg), weight);
 				benchmarking_option_set = true;
 				break;
 			case 'D':
@@ -3155,11 +3202,15 @@ main(int argc, char **argv)
 	if (num_scripts == 0 && !is_init_mode)
 	{
 		addScript(desc, process_builtin(
-					  find_builtin("tpcb-like", &desc), desc));
+					  find_builtin("tpcb-like", &desc), desc), 1);
 		benchmarking_option_set = true;
 		internal_script_used = true;
 	}
 
+	/* compute total_weight */
+	for (i = 0; i < num_scripts; i++)
+		total_weight += sql_script[i].weight;
+
 	/* show per script stats if several scripts are used */
 	if (!initialization_option_set && num_scripts > 1)
 		per_script_stats = true;