#4505 merge 5.5 hot alter table to main refs #4505

git-svn-id: file:///svn/mysql/tokudb-engine/tokudb-engine@45183 c7de825b-a66e-492c-adef-691d508d4ae1

storage/tokudb/ha_tokudb_alter_55.cc

@@ -199,7 +199,9 @@ ha_tokudb::prepare_for_alter() {
 bool
 ha_tokudb::try_hot_alter_table() {
     TOKUDB_DBUG_ENTER("try_hot_alter_table");
-    DBUG_RETURN(true);
+    THD *thd = ha_thd();
+    bool disable_hot_alter = get_disable_hot_alter(thd);
+    DBUG_RETURN(!disable_hot_alter);
 }
 
 #endif

storage/tokudb/ha_tokudb_alter_56.cc

@@ -731,12 +731,12 @@ ha_tokudb::check_if_supported_inplace_alter(TABLE *altered_table, Alter_inplace_
     // alter auto_increment (and nothing else)
     if (ha_alter_info->handler_flags == Alter_inplace_info::CHANGE_CREATE_OPTION && 
         create_info->used_fields == HA_CREATE_USED_AUTO) {
-        result = HA_ALTER_INPLACE_NO_LOCK;
+        result = HA_ALTER_INPLACE_EXCLUSIVE_LOCK;
     } else    
     // alter row_format (and nothing else)
     if (ha_alter_info->handler_flags == Alter_inplace_info::CHANGE_CREATE_OPTION && 
         create_info->used_fields == HA_CREATE_USED_ROW_FORMAT) {
-        result = HA_ALTER_INPLACE_NO_LOCK;
+        result = HA_ALTER_INPLACE_EXCLUSIVE_LOCK;
     } else    
     // add index (and nothing else)
     if (ha_alter_info->handler_flags == Alter_inplace_info::ADD_INDEX || 
@@ -746,7 +746,7 @@ ha_tokudb::check_if_supported_inplace_alter(TABLE *altered_table, Alter_inplace_
         // someday, allow multiple hot indexes via alter table add key. don't forget to change the store_lock function.
         // for now, hot indexing is only supported via session variable with the create index sql command
         if (get_create_index_online(thd) && ha_alter_info->index_add_count == 1 && thd_sql_command(thd) == SQLCOM_CREATE_INDEX) 
-            result = HA_ALTER_INPLACE_NO_LOCK_AFTER_PREPARE;
+            result = HA_ALTER_INPLACE_NO_LOCK;
     } else
     // drop index (and nothing else)
     if (ha_alter_info->handler_flags == Alter_inplace_info::DROP_INDEX ||

storage/tokudb/hatoku_hton.cc

@@ -77,6 +77,13 @@ static MYSQL_THDVAR_BOOL(disable_slow_alter,
   NULL, 
   FALSE
   );
+static MYSQL_THDVAR_BOOL(disable_hot_alter,
+  0,
+  "if on, hot alter table is disabled",
+  NULL, 
+  NULL, 
+  FALSE
+  );
 static MYSQL_THDVAR_BOOL(create_index_online,
   0,
   "if on, create index done online",
@@ -692,6 +699,10 @@ bool get_disable_slow_alter(THD* thd) {
     return (THDVAR(thd, disable_slow_alter) != 0);
 }
 
+bool get_disable_hot_alter(THD* thd) {
+    return THDVAR(thd, disable_hot_alter) != 0;
+}
+
 bool get_create_index_online(THD* thd) {
     return (THDVAR(thd, create_index_online) != 0);
 }
@@ -1616,6 +1627,7 @@ static struct st_mysql_sys_var *tokudb_system_variables[] = {
     MYSQL_SYSVAR(pk_insert_mode),
     MYSQL_SYSVAR(load_save_space),
     MYSQL_SYSVAR(disable_slow_alter),
+    MYSQL_SYSVAR(disable_hot_alter),
     MYSQL_SYSVAR(create_index_online),
     MYSQL_SYSVAR(disable_prefetching),
     MYSQL_SYSVAR(version),

storage/tokudb/hatoku_hton.h

@@ -24,6 +24,7 @@ typedef enum srv_row_format_enum srv_row_format_t;
 uint get_pk_insert_mode(THD* thd);
 bool get_load_save_space(THD* thd);
 bool get_disable_slow_alter(THD* thd);
+bool get_disable_hot_alter(THD* thd);
 bool get_create_index_online(THD* thd);
 bool get_disable_prefetching(THD* thd);
 bool get_prelock_empty(THD* thd);