MDEV-7586: Merged derived tables/VIEWs increment created_tmp_tables

Temporary table count fix. The number of temporary tables was increased
when the table is not actually created. (when do_not_open was passed
as TRUE to create_tmp_table).

mysql-test/r/tmp_table_count-7586.result

@@ -0,0 +1,83 @@
+create table t2 (a int);
+insert into t2 values (1),(2),(3);
+create view v2 as select a from t2;
+flush status;
+select * from v2;
+a
+1
+2
+3
+show status like '%Created_tmp%';
+Variable_name	Value
+Created_tmp_disk_tables	0
+Created_tmp_files	0
+Created_tmp_tables	0
+explain select * from v2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	3	
+select * from (select * from t2) T1;
+a
+1
+2
+3
+show status like '%Created_tmp%';
+Variable_name	Value
+Created_tmp_disk_tables	0
+Created_tmp_files	0
+Created_tmp_tables	0
+explain select * from (select * from t2) T1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	3	
+drop view v2;
+drop table t2;
+CREATE TABLE t1(a int);
+INSERT INTO t1 values(1),(2);
+CREATE TABLE t2(a int);
+INSERT INTO t2 values(1),(2);
+EXPLAIN SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a HAVING a > 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	test.t1.a	1	
+2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	2	Using temporary
+truncate table performance_schema.events_statements_history_long;
+flush status;
+CREATE TABLE t3 SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a HAVING a > 1);
+# Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+sum(created_tmp_tables)
+2
+show status like '%Created_tmp%';
+Variable_name	Value
+Created_tmp_disk_tables	0
+Created_tmp_files	0
+Created_tmp_tables	2
+drop table t3;
+EXPLAIN SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	func	1	
+2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	2	
+truncate table performance_schema.events_statements_history_long;
+flush status;
+CREATE TABLE t3 SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a);
+# Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+sum(created_tmp_tables)
+1
+show status like '%Created_tmp%';
+Variable_name	Value
+Created_tmp_disk_tables	0
+Created_tmp_files	0
+Created_tmp_tables	1
+drop table t1,t2,t3;
+truncate table performance_schema.events_statements_history_long;
+flush status;
+# Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+sum(created_tmp_tables)
+0
+show status like '%Created_tmp%';
+Variable_name	Value
+Created_tmp_disk_tables	0
+Created_tmp_files	0
+Created_tmp_tables	0

mysql-test/t/tmp_table_count-7586.test

@@ -0,0 +1,53 @@
+# MDEV-7586 regression test.
+# Test if created_tmp_tables status variable is correctly incremented.
+--source include/have_perfschema.inc
+
+create table t2 (a int);
+insert into t2 values (1),(2),(3);
+create view v2 as select a from t2;
+
+flush status;
+select * from v2;
+show status like '%Created_tmp%';
+
+explain select * from v2;
+
+select * from (select * from t2) T1;
+show status like '%Created_tmp%';
+
+explain select * from (select * from t2) T1;
+
+
+drop view v2;
+drop table t2;
+
+
+CREATE TABLE t1(a int);
+INSERT INTO t1 values(1),(2);
+CREATE TABLE t2(a int);
+INSERT INTO t2 values(1),(2);
+
+EXPLAIN SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a HAVING a > 1);
+truncate table performance_schema.events_statements_history_long;
+flush status;
+CREATE TABLE t3 SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a HAVING a > 1);
+--echo # Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+show status like '%Created_tmp%';
+drop table t3;
+
+EXPLAIN SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a);
+truncate table performance_schema.events_statements_history_long;
+flush status;
+CREATE TABLE t3 SELECT * FROM t1 WHERE a IN (SELECT * FROM t2 GROUP BY a);
+--echo # Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+show status like '%Created_tmp%';
+
+drop table t1,t2,t3;
+
+truncate table performance_schema.events_statements_history_long;
+flush status;
+--echo # Performance schema should be the same as "Created_tmp_tables" variable below
+select sum(created_tmp_tables) from performance_schema.events_statements_history_long;
+show status like '%Created_tmp%';

sql/opt_subselect.cc

@@ -3890,7 +3890,6 @@ SJ_TMP_TABLE::create_sj_weedout_tmp_table(THD *thd)
   /*
     STEP 1: Get temporary table name
   */
-  thd->inc_status_created_tmp_tables();
   if (use_temp_pool && !(test_flags & TEST_KEEP_TMP_TABLES))
     temp_pool_slot = bitmap_lock_set_next(&temp_pool);
 

sql/sql_select.cc

@@ -15809,7 +15809,6 @@ create_tmp_table(THD *thd, TMP_TABLE_PARAM *param, List<Item> &fields,
               (int) distinct, (int) save_sum_fields,
               (ulong) rows_limit, MY_TEST(group)));
 
-  thd->inc_status_created_tmp_tables();
   thd->query_plan_flags|= QPLAN_TMP_TABLE;
 
   if (use_temp_pool && !(test_flags & TEST_KEEP_TMP_TABLES))
@@ -16763,14 +16762,19 @@ bool open_tmp_table(TABLE *table)
                                    HA_OPEN_TMP_TABLE |
                                    HA_OPEN_INTERNAL_TABLE)))
   {
-    table->file->print_error(error,MYF(0)); /* purecov: inspected */
+    table->file->print_error(error, MYF(0)); /* purecov: inspected */
-    table->db_stat=0;
+    table->db_stat= 0;
-    return(1);
+    return 1;
   }
   table->db_stat= HA_OPEN_KEYFILE+HA_OPEN_RNDFILE;
-  (void) table->file->extra(HA_EXTRA_QUICK);		/* Faster */
+  (void) table->file->extra(HA_EXTRA_QUICK); /* Faster */
-  table->created= TRUE;
+  if (!table->created)
-  return(0);
+  {
+    table->created= TRUE;
+    table->in_use->inc_status_created_tmp_tables();
+  }
+
+  return 0;
 }
 
 
@@ -16937,8 +16941,10 @@ bool create_internal_tmp_table(TABLE *table, KEY *keyinfo,
     goto err;
   }
   table->in_use->inc_status_created_tmp_disk_tables();
+  table->in_use->inc_status_created_tmp_tables();
   table->in_use->query_plan_flags|= QPLAN_TMP_DISK;
   share->db_record_offset= 1;
+  table->created= TRUE;
   DBUG_RETURN(0);
  err:
   DBUG_RETURN(1);
@@ -17083,6 +17089,7 @@ bool create_internal_tmp_table(TABLE *table, KEY *keyinfo,
     goto err;
   }
   table->in_use->inc_status_created_tmp_disk_tables();
+  table->in_use->inc_status_created_tmp_tables();
   table->in_use->query_plan_flags|= QPLAN_TMP_DISK;
   share->db_record_offset= 1;
   table->created= TRUE;

sql/sql_select.h

@@ -1788,10 +1788,6 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
 			bool table_cant_handle_bit_fields,
                         bool make_copy_field,
                         uint convert_blob_length);
-bool create_internal_tmp_table(TABLE *table, KEY *keyinfo, 
-                               TMP_ENGINE_COLUMNDEF *start_recinfo,
-                               TMP_ENGINE_COLUMNDEF **recinfo, 
-                               ulonglong options, my_bool big_tables);
 
 /*
   General routine to change field->ptr of a NULL-terminated array of Field