Merge maint1.mysql.com:/data/localhome/tsmith/bk/mrg50-c

into  maint1.mysql.com:/data/localhome/tsmith/bk/mrg51-c

mysql-test/r/warnings.result

@@ -166,6 +166,20 @@ show variables like 'max_error_count';
 Variable_name	Value
 max_error_count	10
 drop table t1;
+create table t1 (id int) engine=merge;
+Warnings:
+Warning	1266	Using storage engine MyISAM for table 't1'
+alter table t1 engine=merge;
+Warnings:
+Warning	1266	Using storage engine MyISAM for table 't1'
+drop table t1;
+create table t1 (id int) type=heap;
+Warnings:
+Warning	1287	'TYPE=storage_engine' is deprecated; use 'ENGINE=storage_engine' instead
+alter table t1 type=myisam;
+Warnings:
+Warning	1287	'TYPE=storage_engine' is deprecated; use 'ENGINE=storage_engine' instead
+drop table t1;
 set table_type=MYISAM;
 Warnings:
 Warning	1541	The syntax 'table_type' is deprecated and will be removed in MySQL 5.2. Please use 'storage_engine' instead.

mysql-test/t/warnings-master.opt

---skip-isam
+--skip-isam --skip-merge

mysql-test/t/warnings.test

@@ -116,6 +116,9 @@ drop table t1;
 #create table t1 (id int) engine=isam;
 #alter table t1 engine=isam;
 #drop table t1;
+create table t1 (id int) engine=merge;
+alter table t1 engine=merge;
+drop table t1;
 
 #
 # Test for deprecated table_type variable

sql/mysql_priv.h

@@ -1669,6 +1669,10 @@ extern handlerton partition_hton;
 extern SHOW_COMP_OPTION have_partition_db;
 #endif
 
+extern handlerton myisammrg_hton;
+/* MRG_MYISAM handler is always built, but may be skipped */
+#define have_merge_db myisammrg_hton.state
+
 extern handlerton myisam_hton;
 extern handlerton myisammrg_hton;
 extern handlerton heap_hton;

sql/mysqld.cc

@@ -310,7 +310,7 @@ static bool lower_case_table_names_used= 0;
 static bool volatile select_thread_in_use, signal_thread_in_use;
 static bool volatile ready_to_exit;
 static my_bool opt_debugging= 0, opt_external_locking= 0, opt_console= 0;
-static my_bool opt_bdb, opt_isam, opt_ndbcluster;
+static my_bool opt_bdb, opt_isam, opt_ndbcluster, opt_merge;
 static my_bool opt_short_log_format= 0;
 static uint kill_cached_threads, wake_thread;
 static ulong killed_threads, thread_created;
@@ -4838,7 +4838,8 @@ enum options_mysqld
   OPT_LOG_OUTPUT,
   OPT_PORT_OPEN_TIMEOUT,
   OPT_GENERAL_LOG,
-  OPT_SLOW_LOG
+  OPT_SLOW_LOG,
+  OPT_MERGE
 };
 
 
@@ -5346,6 +5347,9 @@ master-ssl",
 #endif /* HAVE_REPLICATION */
   {"memlock", OPT_MEMLOCK, "Lock mysqld in memory.", (gptr*) &locked_in_memory,
    (gptr*) &locked_in_memory, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
+  {"merge", OPT_MERGE, "Enable Merge storage engine. Disable with \
+--skip-merge.",
+   (gptr*) &opt_merge, (gptr*) &opt_merge, 0, GET_BOOL, NO_ARG, 1, 0, 0, 0, 0},
   {"myisam-recover", OPT_MYISAM_RECOVER,
    "Syntax: myisam-recover[=option[,option...]], where option can be DEFAULT, BACKUP, FORCE or QUICK.",
    (gptr*) &myisam_recover_options_str, (gptr*) &myisam_recover_options_str, 0,
@@ -7556,6 +7560,11 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
     global_system_variables.tx_isolation= (type-1);
     break;
   }
+  case OPT_MERGE:
+    if (opt_merge)
+      have_merge_db= SHOW_OPTION_YES;
+    else
+      have_merge_db= SHOW_OPTION_DISABLED;
 #ifdef WITH_BERKELEY_STORAGE_ENGINE
   case OPT_BDB_NOSYNC:
     /* Deprecated option */

sql/set_var.cc

@@ -681,6 +681,7 @@ sys_var_have_variable sys_have_federated_db("have_federated_engine",
                                             &have_federated_db);
 sys_var_have_variable sys_have_geometry("have_geometry", &have_geometry);
 sys_var_have_variable sys_have_innodb("have_innodb", &have_innodb);
+sys_var_have_variable sys_have_merge_db("have_merge", &have_merge_db);
 sys_var_have_variable sys_have_ndbcluster("have_ndbcluster", &have_ndbcluster);
 sys_var_have_variable sys_have_openssl("have_openssl", &have_openssl);
 sys_var_have_variable sys_have_partition_db("have_partitioning",
@@ -821,6 +822,7 @@ SHOW_VAR init_vars[]= {
   {sys_have_federated_db.name,(char*) &have_federated_db,           SHOW_HAVE},
   {sys_have_geometry.name,    (char*) &have_geometry,               SHOW_HAVE},
   {sys_have_innodb.name,      (char*) &have_innodb,                 SHOW_HAVE},
+  {sys_have_merge_db.name,    (char*) &have_merge_db,               SHOW_HAVE},
   {sys_have_ndbcluster.name,  (char*) &have_ndbcluster,             SHOW_HAVE},
   {sys_have_openssl.name,     (char*) &have_openssl,                SHOW_HAVE},
   {sys_have_partition_db.name,(char*) &have_partition_db,           SHOW_HAVE},