Merge

innobase/include/srv0srv.h

@@ -52,7 +52,7 @@ extern ulint*   srv_data_file_is_raw_partition;
 
 extern ibool	srv_auto_extend_last_data_file;
 extern ulint	srv_last_file_size_max;
-extern ulint	srv_auto_extend_increment;
+extern ulong	srv_auto_extend_increment;
 
 extern ibool	srv_created_new_raw;
 
@@ -112,11 +112,9 @@ extern ibool	srv_use_checksums;
 extern ibool    srv_set_thread_priorities;
 extern int      srv_query_thread_priority;
 
-extern ulint	srv_max_purge_lag;
+extern ulong	srv_max_purge_lag;
 extern ibool	srv_use_awe;
 extern ibool	srv_use_adaptive_hash_indexes;
-
-extern ulint	srv_max_purge_lag;
 /*-------------------------------------------*/
 
 extern ulint	srv_n_rows_inserted;

innobase/srv/srv0srv.c

@@ -97,7 +97,7 @@ ulint	srv_last_file_size_max	= 0;		 /* if != 0, this tells
 						 the max size auto-extending
 						 may increase the last data
 						 file size */
-ulint	srv_auto_extend_increment = 8;		 /* If the last data file is
+ulong	srv_auto_extend_increment = 8;		 /* If the last data file is
 						 auto-extended, we add this
 						 many pages to it at a time */
 ulint*  srv_data_file_is_raw_partition = NULL;
@@ -323,9 +323,6 @@ disable adaptive hash indexes */
 ibool	srv_use_awe			= FALSE;
 ibool	srv_use_adaptive_hash_indexes 	= TRUE;
 
-/* Maximum allowable purge history length.  <=0 means 'infinite'. */
-ulint	srv_max_purge_lag		= 0;
-
 /*-------------------------------------------*/
 ulint	srv_n_spin_wait_rounds	= 20;
 ulint srv_n_free_tickets_to_enter = 500;
@@ -972,6 +969,8 @@ srv_general_init(void)
 
 /*======================= InnoDB Server FIFO queue =======================*/
 
+/* Maximum allowable purge history length.  <=0 means 'infinite'. */
+ulong	srv_max_purge_lag		= 0;
 
 /*************************************************************************
 Puts an OS thread to wait if there are too many concurrent threads

myisam/mi_create.c

@@ -558,6 +558,21 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
     create_flag=MY_DELETE_OLD;
   }
 
+  /*
+    If a MRG_MyISAM table is in use, the mapped MyISAM tables are open,
+    but no entry is made in the table cache for them.
+    A TRUNCATE command checks for the table in the cache only and could
+    be fooled to believe, the table is not open.
+    Pull the emergency brake in this situation. (Bug #8306)
+  */
+  if (test_if_reopen(filename))
+  {
+    my_printf_error(0, "MyISAM table '%s' is in use "
+                    "(most likely by a MERGE table). Try FLUSH TABLES.",
+                    MYF(0), name + dirname_length(name));
+    goto err;
+  }
+
   if ((file= my_create_with_symlink(linkname_ptr,
 				    filename,
 				    0, O_RDWR | O_TRUNC,

myisam/mi_open.c

@@ -50,7 +50,7 @@ if (pos > end_pos)             \
 ** In MySQL the server will handle version issues.
 ******************************************************************************/
 
-static MI_INFO *test_if_reopen(char *filename)
+MI_INFO *test_if_reopen(char *filename)
 {
   LIST *pos;
 

myisam/myisamdef.h

@@ -708,6 +708,7 @@ void mi_copy_status(void* to,void *from);
 my_bool mi_check_status(void* param);
 void mi_disable_non_unique_index(MI_INFO *info, ha_rows rows);
 
+extern MI_INFO *test_if_reopen(char *filename);
 my_bool check_table_is_closed(const char *name, const char *where);
 int mi_open_datafile(MI_INFO *info, MYISAM_SHARE *share, File file_to_dup);
 int mi_open_keyfile(MYISAM_SHARE *share);

mysql-test/r/myisam.result

@@ -568,6 +568,24 @@ select count(*) from t1 where a is null;
 count(*)
 2
 drop table t1;
+create table t1 (c1 int, index(c1));
+create table t2 (c1 int, index(c1)) engine=merge union=(t1);
+insert into t1 values (1);
+flush tables;
+select * from t2;
+c1
+1
+flush tables;
+truncate table t1;
+insert into t1 values (1);
+flush tables;
+select * from t2;
+c1
+1
+truncate table t1;
+ERROR HY000: MyISAM table 't1' is in use (most likely by a MERGE table). Try FLUSH TABLES.
+insert into t1 values (1);
+drop table t1,t2;
 set storage_engine=MyISAM;
 drop table if exists t1,t2,t3;
 --- Testing varchar ---

mysql-test/t/myisam.test

@@ -527,6 +527,32 @@ explain select count(*) from t1 where a is null;
 select count(*) from t1 where a is null;
 drop table t1;
 
+#
+# Bug #8306: TRUNCATE leads to index corruption 
+#
+create table t1 (c1 int, index(c1));
+create table t2 (c1 int, index(c1)) engine=merge union=(t1);
+insert into t1 values (1);
+# Close all tables.
+flush tables;
+# Open t2 and (implicitly) t1.
+select * from t2;
+# Truncate after flush works (unless another threads reopens t2 in between).
+flush tables;
+truncate table t1;
+insert into t1 values (1);
+# Close all tables.
+flush tables;
+# Open t2 and (implicitly) t1.
+select * from t2;
+# Truncate t1, wich was not recognized as open without the bugfix.
+# Now, it should fail with a table-in-use error message.
+--error 1105
+truncate table t1;
+# The insert used to fail on the crashed table.
+insert into t1 values (1);
+drop table t1,t2;
+
 #
 # Test varchar
 #

sql/ha_innodb.cc

@@ -2631,7 +2631,9 @@ ha_innobase::write_row(
         if (table->timestamp_field_type & TIMESTAMP_AUTO_SET_ON_INSERT)
                 table->timestamp_field->set_time();
 
-	if (user_thd->lex->sql_command == SQLCOM_ALTER_TABLE
+	if ((user_thd->lex->sql_command == SQLCOM_ALTER_TABLE
+	    || user_thd->lex->sql_command == SQLCOM_CREATE_INDEX
+	    || user_thd->lex->sql_command == SQLCOM_DROP_INDEX)
 	    && num_write_row >= 10000) {
 		/* ALTER TABLE is COMMITted at every 10000 copied rows.
 		The IX table lock for the original table has to be re-issued.

sql/ha_innodb.h

@@ -239,7 +239,6 @@ extern ulong srv_auto_extend_increment;
 extern ulong srv_n_spin_wait_rounds;
 extern ulong srv_n_free_tickets_to_enter;
 extern ulong srv_thread_sleep_delay;
-extern ulong srv_max_purge_lag;
 extern ulong srv_thread_concurrency;
 }