1DROP TABLE IF EXISTS t1;
2CREATE TEMPORARY TABLE t1 (a INT) ENGINE=InnoDB;
3INSERT INTO t1 VALUES (1), (2), (3);
4SET DEBUG_SYNC= 'start_ha_write_row SIGNAL write_in_progress WAIT_FOR i_s_completed';
5ALTER TABLE t1 ADD COLUMN b VARCHAR(10);
6SET DEBUG_SYNC= 'now WAIT_FOR write_in_progress';
7SELECT COUNT(*) FROM INFORMATION_SCHEMA.GLOBAL_TEMPORARY_TABLES;
8COUNT(*)
92
10SET DEBUG_SYNC= 'now SIGNAL i_s_completed';
11DROP TABLE t1;
12SET DEBUG_SYNC='reset';
13