CREATE TABLE t1 (a INT, b VARCHAR(10)) ENGINE=InnoDB
STATS_PERSISTENT=1 STATS_AUTO_RECALC=0
PARTITION BY RANGE(a)
(PARTITION pa VALUES LESS THAN (3),
PARTITION pb VALUES LESS THAN (5));
INSERT INTO t1 VALUES(2,'two'),(2,'two'),(4,'four');
connect ddl,localhost,root,,test;
SET DEBUG_SYNC = 'inplace_after_index_build SIGNAL go WAIT_FOR done';
ALTER TABLE t1 ADD UNIQUE KEY (a,b(3));
connection default;
SET DEBUG_SYNC = 'now WAIT_FOR go';
BEGIN;
SELECT * FROM t1 FOR UPDATE;
a	b
2	two
2	two
4	four
SET DEBUG_SYNC = 'now SIGNAL done';
connection ddl;
ERROR 23000: Duplicate entry '2-two' for key 'a'
connection default;
DELETE FROM t1;
SET DEBUG_SYNC = 'RESET';
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
CREATE TABLE t(a INT, b VARCHAR(10)) ENGINE=InnoDB
STATS_PERSISTENT=1 STATS_AUTO_RECALC=1;
RENAME TABLE t TO u;
DELETE FROM mysql.innodb_table_stats WHERE table_name='u';
DELETE FROM mysql.innodb_index_stats WHERE table_name='u';
SET STATEMENT debug_dbug='+d,dict_stats_save_exit_notify_and_wait' FOR
SELECT * FROM u;
connection ddl;
SET DEBUG_SYNC='open_tables_after_open_and_process_table
WAIT_FOR dict_stats_save_finished';
ALTER TABLE t1 EXCHANGE PARTITION pb WITH TABLE u;
connect sync,localhost,root;
SET DEBUG_SYNC='now SIGNAL dict_stats_save_unblock';
disconnect sync;
connection default;
a	b
connection ddl;
disconnect ddl;
connection default;
SELECT * FROM u;
a	b
SET DEBUG_SYNC = 'RESET';
DROP TABLE t1,u;