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DROP TABLE IF EXISTS t1;
DROP TABLE IF EXISTS t2;
CREATE TABLE t2 (a INT);
INSERT INTO t2 VALUES(10);
INSERT INTO t2 VALUES(10);
INSERT INTO t2 VALUES(20);
INSERT INTO t2 VALUES(10);
INSERT INTO t2 VALUES(20);
SET DEBUG_SYNC= 'locked_table_name SIGNAL thread1_ready WAIT_FOR threads_dumped';
CREATE TABLE t1 (a INT);
SET DEBUG_SYNC= 'now WAIT_FOR thread1_ready';
SET DEBUG_SYNC= 'execute_command_after_close_tables SIGNAL thread2_ready WAIT_FOR threads_dumped';
SELECT a FROM t2 WHERE a > 15;
SET DEBUG_SYNC= 'now WAIT_FOR thread2_ready';
SHOW PROCESSLIST;
Id User Host db Command Time State Info Rows_sent Rows_examined Rows_read
### root ### test Query ### ### SHOW PROCESSLIST 0 0 2
### root ### test Query ### ### CREATE TABLE t1 (a INT) 0 0 1
### root ### test Query ### ### SELECT a FROM t2 WHERE a > 15 2 5 6
SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id;
id info rows_sent rows_examined rows_read
### SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id 0 0 1
### CREATE TABLE t1 (a INT) 0 0 1
### SELECT a FROM t2 WHERE a > 15 2 5 6
SET DEBUG_SYNC= 'now SIGNAL threads_dumped';
a
20
20
SET DEBUG_SYNC= 'sent_row SIGNAL thread1_ready WAIT_FOR threads_dumped';
SELECT a FROM t2 WHERE a < 15;
SET DEBUG_SYNC= 'now WAIT_FOR thread1_ready';
SET DEBUG_SYNC= 'sent_row SIGNAL thread2_ready WAIT_FOR threads_dumped';
SELECT a FROM t2 WHERE a > 15;
SET DEBUG_SYNC= 'now WAIT_FOR thread2_ready';
SHOW PROCESSLIST;
Id User Host db Command Time State Info Rows_sent Rows_examined Rows_read
### root ### test Query ### ### SHOW PROCESSLIST 0 0 4
### root ### test Query ### ### SELECT a FROM t2 WHERE a < 15 1 0 1
### root ### test Query ### ### SELECT a FROM t2 WHERE a > 15 1 0 3
SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id;
id info rows_sent rows_examined rows_read
### SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id 0 0 1
### SELECT a FROM t2 WHERE a < 15 1 0 1
### SELECT a FROM t2 WHERE a > 15 1 0 3
SET DEBUG_SYNC= 'now SIGNAL threads_dumped';
a
10
10
10
a
20
20
SET DEBUG_SYNC= 'execute_command_after_close_tables SIGNAL thread1_ready WAIT_FOR threads_dumped';
UPDATE t2 SET a = 15 WHERE a = 20;
SET DEBUG_SYNC= 'now WAIT_FOR thread1_ready';
SET DEBUG_SYNC= 'execute_command_after_close_tables SIGNAL thread2_ready WAIT_FOR threads_dumped';
UPDATE t2 SET a = 15 WHERE a = 10;
SET DEBUG_SYNC= 'now WAIT_FOR thread2_ready';
SHOW PROCESSLIST;
Id User Host db Command Time State Info Rows_sent Rows_examined Rows_read
### root ### test Query ### ### SHOW PROCESSLIST 0 0 4
### root ### test Query ### ### UPDATE t2 SET a = 15 WHERE a = 20 0 5 6
### root ### test Query ### ### UPDATE t2 SET a = 15 WHERE a = 10 0 5 6
SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id;
id info rows_sent rows_examined rows_read
### SELECT id, info, rows_sent, rows_examined, rows_read FROM INFORMATION_SCHEMA.PROCESSLIST ORDER BY id 0 0 1
### UPDATE t2 SET a = 15 WHERE a = 20 0 5 6
### UPDATE t2 SET a = 15 WHERE a = 10 0 5 6
SET DEBUG_SYNC= 'now SIGNAL threads_dumped';
DROP TABLES t1, t2;
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