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|
#
# 1. Test MAX_EXECUTION_TIME option syntax.
#
CREATE TABLE t1 (a INT);
INSERT INTO t1 VALUES (10);
SET @var= (SELECT /*+ MAX_EXECUTION_TIME(0) */ 1);
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT 1 FROM t1 WHERE a IN (SELECT /*+ MAX_EXECUTION_TIME(0) */ 1);
1
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT (SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
(SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1)
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT a FROM t1 WHERE a IN (SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT * FROM t1 WHERE a IN (SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1
WHERE a IN (SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT * FROM t1
WHERE a IN (SELECT a FROM t1 UNION SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1
WHERE a IN (SELECT a FROM t1 UNION SELECT /*+ MAX_EXECUTION_TIME(0) */ a FROM t1);
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT * FROM t1 UNION SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1;
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1
UNION SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1;
a
10
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
INSERT INTO t1 SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1;
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
CREATE TABLE t2 AS SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1;
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
CREATE TABLE t3 AS SELECT 1 A UNION SELECT 2 UNION SELECT /*+ MAX_EXECUTION_TIME(0) */ 3;
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
CREATE TABLE /*+ MAX_EXECUTION_TIME(100) */ t4 (a int);
CREATE /*+ MAX_EXECUTION_TIME(100) */ TABLE t5 (a int);
DELETE /*+ MAX_EXECUTION_TIME(100) */ FROM t1;
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
UPDATE /*+ MAX_EXECUTION_TIME(100) */ t1 SET a=20;
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
ALTER TABLE /*+ MAX_EXECUTION_TIME(100) */ t1 ADD b VARCHAR(200);
ALTER /*+ MAX_EXECUTION_TIME(100) */ TABLE t1 ADD c VARCHAR(200);
SELECT /*+ MAX_EXECUTION_TIME(0) */ * FROM t1;
a b c
DROP TABLE t1, t2, t3, t4, t5;
#
# 2. Test MAX_EXECUTION_TIME value set at session level.
#
SELECT @@max_execution_time;
@@max_execution_time
0
SET @@SESSION.max_execution_time= 1000;
SELECT @@max_execution_time;
@@max_execution_time
1000
SET @@SESSION.max_execution_time= 0;
#
# 3. Test the MAX_EXECUTION_TIME option by setting value for it at,
# - STATEMENT
# - SESSION
#
SELECT /*+ MAX_EXECUTION_TIME(1000) */ SLEEP(5);
SLEEP(5)
1
SET @@SESSION.max_execution_time= 1000;
SELECT SLEEP(5);
SLEEP(5)
1
SET @@SESSION.max_execution_time= 0;
#
# 4. Test statement timeout functionality.
#
CREATE TABLE t1 (a INT, b VARCHAR(300));
INSERT INTO t1 VALUES (1, 'string');
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
SET @@SESSION.max_execution_time= 2;
SELECT *, SLEEP(0.5) from t1;
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
LOCK TABLE t1 WRITE;
SELECT * FROM t1;
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
SELECT /*+ MAX_EXECUTION_TIME(1) */ * FROM t1;
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
UNLOCK TABLES;
CREATE TABLE t2 SELECT * FROM t1;
ALTER TABLE t2 ADD c VARCHAR(200) default 'new_col';
UPDATE t1 SET b= 'new_string';
INSERT INTO t1 SELECT * FROM t1;
DELETE FROM t2;
#
# 5. Test SELECT with subquery.
#
SELECT /*+ MAX_EXECUTION_TIME(3600000) */ (SELECT SLEEP(0.5)) AS true_if_subquery_is_timedout;
true_if_subquery_is_timedout
0
#
# 6. Test max_execution_time with prepared statements.
#
PREPARE stmt1 FROM "SELECT *, SLEEP(0.5) FROM t1 WHERE b= 'new_string'";
PREPARE stmt2 FROM "SELECT /*+ MAX_EXECUTION_TIME(2) */ *, SLEEP(0.5) FROM t1 WHERE b= 'new_string'";
PREPARE stmt3 FROM "SELECT /*+ MAX_EXECUTION_TIME(3600000) */ count(*) FROM t1";
EXECUTE stmt1;
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
EXECUTE stmt2;
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
EXECUTE stmt3;
count(*)
4096
DEALLOCATE PREPARE stmt1;
DEALLOCATE PREPARE stmt2;
DEALLOCATE PREPARE stmt3;
#
# 7. Test max_execution_time with Stored Routines.
#
CREATE FUNCTION f1() RETURNS INT
BEGIN
SELECT /*+ MAX_EXECUTION_TIME(1) */ SLEEP(1.5) INTO @a;
RETURN 1;
END|
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
DROP FUNCTION f1|
CREATE FUNCTION f1() RETURNS INT
BEGIN
SELECT SLEEP(3) INTO @a;
RETURN 1;
END|
CREATE FUNCTION f2() RETURNS INT
BEGIN
INSERT INTO t2 SELECT * FROM t2;
RETURN 1;
END|
INSERT INTO t2 VALUES (1, 'string1', 'string2');
SET @@SESSION.max_execution_time= 2;
SELECT f1();
ERROR HY000: Query execution was interrupted, maximum statement execution time exceeded
SELECT /*+ MAX_EXECUTION_TIME(60000) */ f2();
f2()
1
Warnings:
Note 3025 Select is not a read only statement, disabling timer
DROP FUNCTION f1;
DROP FUNCTION f2;
CREATE PROCEDURE p1()
BEGIN
SELECT /*+ MAX_EXECUTION_TIME(1) */ SLEEP(1.5);
INSERT INTO t2 SELECT DISTINCT * FROM t2;
END|
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
DROP PROCEDURE p1|
CREATE PROCEDURE p1()
BEGIN
INSERT INTO t2 SELECT DISTINCT * FROM t2;
SELECT SLEEP(3);
END|
CALL p1();
SLEEP(3)
0
DROP PROCEDURE p1;
DROP TABLE t2;
SET @global_event_scheduler_status= @@global.event_scheduler;
SET @@global.event_scheduler= ON;
SET @@global.max_execution_time= 1000;
CREATE TABLE t2 (f1 int, f2 int);
SELECT SLEEP(5) into @a;
SELECT @a;
@a
1
CREATE EVENT event1 ON SCHEDULE AT CURRENT_TIMESTAMP
DO BEGIN
SELECT SLEEP(2) into @a;
SELECT /*+ MAX_EXECUTION_TIME(1) */ SLEEP(2) into @b;
INSERT INTO t2 VALUES(@a, @b);
END|
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
# Wait until at least one instance of event is executed.
SELECT /*+ MAX_EXECUTION_TIME(3600000) */ * FROM t2;
f1 f2
0 0
DELETE FROM t2;
SET @@global.event_scheduler= @global_event_scheduler_status;
SET @@global.max_execution_time= 0;
CREATE TABLE t3 (f1 int)|
CREATE TRIGGER t1_before_trigger BEFORE INSERT ON t1 FOR EACH ROW
BEGIN
SELECT SLEEP(2) into @a;
SELECT /*+ MAX_EXECUTION_TIME(1) */ SLEEP(2) into @b;
INSERT INTO t3 VALUES(@a);
INSERT INTO t3 VALUES(@b);
END|
Warnings:
Warning 3125 MAX_EXECUTION_TIME hint is supported by top-level standalone SELECT statements only
DROP TRIGGER t1_before_trigger|
CREATE TRIGGER t1_before_trigger BEFORE INSERT ON t1 FOR EACH ROW
BEGIN
SELECT SLEEP(2) into @a;
INSERT INTO t3 VALUES(@a);
END
|
SELECT SLEEP(5) into @a;
SELECT /*+ MAX_EXECUTION_TIME(1000) */ SLEEP(2) into @b;
SELECT @a, @b;
@a @b
1 1
INSERT INTO t1 VALUES (1, 'string');
SELECT /*+ MAX_EXECUTION_TIME(3600000) */ * FROM t3;
f1
0
DROP TABLE t1,t2,t3;
#
# 8. Test MAX_EXECUTION_TIME precedence set at different levels.
#
SET @@SESSION.max_execution_time= 1000;
SELECT sleep(5);
sleep(5)
1
SELECT /*+ MAX_EXECUTION_TIME(20000) */ sleep(5);
sleep(5)
0
SET @@SESSION.max_execution_time= 0;
#
# 9. MAX_EXECUTION_TIME status variables.
#
SELECT CONVERT(VARIABLE_VALUE, UNSIGNED) INTO @time_set
FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET';
SELECT CONVERT(VARIABLE_VALUE, UNSIGNED) INTO @time_exceeded
FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_EXCEEDED';
SELECT /*+ MAX_EXECUTION_TIME(10) */ SLEEP(1);
SLEEP(1)
1
# Ensure that the counters for:
# - statements that are time limited; and
# - statements that exceeded their maximum execution time
# are incremented.
SELECT 1 AS STATUS FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET'
AND CONVERT(VARIABLE_VALUE, UNSIGNED) > @time_set;
STATUS
1
SELECT 1 AS STATUS FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_EXCEEDED'
AND CONVERT(VARIABLE_VALUE, UNSIGNED) > @time_exceeded;
STATUS
1
SELECT CONVERT(VARIABLE_VALUE, UNSIGNED) INTO @time_set_failed
FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET_FAILED';
SET DEBUG= '+d,thd_timer_create_failure';
SELECT /*+ MAX_EXECUTION_TIME(10) */ SLEEP(1);
SLEEP(1)
0
SET DEBUG= '-d,thd_timer_create_failure';
SELECT 1 AS STATUS FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET_FAILED'
AND CONVERT(VARIABLE_VALUE, UNSIGNED) > @time_set_failed;
STATUS
1
SELECT CONVERT(VARIABLE_VALUE, UNSIGNED) INTO @time_set_failed
FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET_FAILED';
SET DEBUG= '+d,thd_timer_set_failure';
SELECT /*+ MAX_EXECUTION_TIME(10) */ SLEEP(1);
SLEEP(1)
0
SET DEBUG= '-d,thd_timer_set_failure';
SELECT 1 AS STATUS FROM performance_schema.global_status
WHERE VARIABLE_NAME= 'MAX_EXECUTION_TIME_SET_FAILED'
AND CONVERT(VARIABLE_VALUE, UNSIGNED) > @time_set_failed;
STATUS
1
SET @@SESSION.max_execution_time= 0;
|
