set @start_read_only= @@global.read_only; set @start_autocommit= @@global.autocommit; set default_storage_engine= innodb; set @@global.autocommit= 0;
CREATE USER test@localhost;
grant CREATE, SELECT, UPDATE, INSERT on *.* to test@localhost;
CREATE USER test2@localhost;
grant CREATE, SELECT, UPDATE on *.* to test2@localhost;
CREATE TABLE t1 (
a char(2) NOT NULL,
b char(2) NOT NULL,
c int(10) unsigned NOT NULL,
d varchar(255) DEFAULT NULL,
e varchar(1000) DEFAULT NULL,
PRIMARY KEY (a, b, c),
KEY (a),
KEY (a, b)
) charset latin1 PARTITION BY KEY (a) PARTITIONS 20;
INSERT INTO t1 (a, b, c, d, e) VALUES
('07', '03', 343, '1', '07_03_343'),
('01', '04', 343, '2', '01_04_343'),
('01', '06', 343, '3', '01_06_343'),
('01', '07', 343, '4', '01_07_343'),
('01', '08', 343, '5', '01_08_343'),
('01', '09', 343, '6', '01_09_343'),
('03', '03', 343, '7', '03_03_343'),
('03', '06', 343, '8', '03_06_343'),
('03', '07', 343, '9', '03_07_343'),
('04', '03', 343, '10', '04_03_343'),
('04', '06', 343, '11', '04_06_343'),
('05', '03', 343, '12', '05_03_343'),
('11', '03', 343, '13', '11_03_343'),
('11', '04', 343, '14', '11_04_343') ;
CREATE TABLE t2 (a int, name VARCHAR(50), purchased DATE)
PARTITION BY RANGE (a)
(PARTITION p0 VALUES LESS THAN (3),
PARTITION p1 VALUES LESS THAN (7),
PARTITION p2 VALUES LESS THAN (9),
PARTITION p3 VALUES LESS THAN (11));
INSERT INTO t2 VALUES
(1, 'desk organiser', '2003-10-15'),
(2, 'CD player', '1993-11-05'),
(3, 'TV set', '1996-03-10'),
(4, 'bookcase', '1982-01-10'),
(5, 'exercise bike', '2004-05-09'),
(6, 'sofa', '1987-06-05'),
(7, 'popcorn maker', '2001-11-22'),
(8, 'acquarium', '1992-08-04'),
(9, 'study desk', '1984-09-16'),
(10, 'lava lamp', '1998-12-25');
CREATE TABLE t3 SELECT * FROM t1;
ALTER TABLE t3 ADD PRIMARY KEY (d);
ALTER TABLE t3 ADD KEY (a);
ALTER TABLE t3 ADD KEY (a, b);
ANALYZE TABLE t3;
Table Op Msg_type Msg_text
test.t3 analyze status Engine-independent statistics collected
test.t3 analyze status OK
########################################################################
connect con1,localhost,test,,test;
BEGIN;
SELECT d,a,b,c FROM t1 partition (p0);
d a b c
SELECT d,a,b,c FROM t1 partition (p1);
d a b c 70303343 80306343 90307343
SELECT d,a,b,c FROM t1 partition (p2);
d a b c
SELECT d,a,b,c FROM t1 partition (p3);
d a b c
SELECT d,a,b,c FROM t1 partition (p4);
d a b c
SELECT d,a,b,c FROM t1 partition (p5);
d a b c
SELECT d,a,b,c FROM t1 partition (p6);
d a b c
SELECT d,a,b,c FROM t1 partition (p7);
d a b c
SELECT d,a,b,c FROM t1 partition (p8);
d a b c
SELECT d,a,b,c FROM t1 partition (p9);
d a b c 20104343 30106343 40107343 50108343 60109343 100403343 110406343 120503343
SELECT d,a,b,c FROM t1 partition (p10);
d a b c
SELECT d,a,b,c FROM t1 partition (p11);
d a b c 131103343 141104343
SELECT d,a,b,c FROM t1 partition (p12);
d a b c
SELECT d,a,b,c FROM t1 partition (p13);
d a b c
SELECT d,a,b,c FROM t1 partition (p14);
d a b c
SELECT d,a,b,c FROM t1 partition (p15);
d a b c
SELECT d,a,b,c FROM t1 partition (p16);
d a b c
SELECT d,a,b,c FROM t1 partition (p17);
d a b c 10703343
SELECT d,a,b,c FROM t1 partition (p18);
d a b c
SELECT d,a,b,c FROM t1 partition (p19);
d a b c
SELECT * FROM t1 WHERE a='01' FOR UPDATE ;
a b c d e 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343
SELECT * FROM t3 FORCE INDEX(a) WHERE a='01' FOR UPDATE ;
a b c d e 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343
connect con2,localhost,test,,test;
BEGIN; SET SESSION innodb_lock_wait_timeout=1;
#
# SHARE ...
SELECT * FROM t1 LOCK IN SHARE MODE; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 LOCK IN SHARE MODE NOWAIT; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
a b c d e 0703343107_03_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 11033431311_03_343 11043431411_04_343 0303343703_03_343 0306343803_06_343 0307343903_07_343
SELECT a,count(b) FROM t1 force index (a) GROUP BY a ORDER BY a LOCK IN SHARE MODE SKIP LOCKED;
a count(b) 015 033 042 051 071 112
SELECT d,a,b,c FROM t1 partition (p1,p9,p11,p17) ORDER BY d
LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
SELECT d,a,b,c FROM t1 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
ANALYZE TABLE t3;
Table Op Msg_type Msg_text
test.t3 analyze status Engine-independent statistics collected
test.t3 analyze status OK
SELECT d,a,b,c FROM t3 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
explain SELECT d,a,b,c FROM t3 ORDER BY d
LOCK IN SHARE MODE SKIP LOCKED;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t3 index NULL PRIMARY 257 NULL 14
#
# UPDATE ...
SELECT * FROM t1 FOR UPDATE; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 FOR UPDATE NOWAIT; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 ORDER BY a FOR UPDATE SKIP LOCKED;
a b c d e 0303343703_03_343 0306343803_06_343 0307343903_07_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 0703343107_03_343 11033431311_03_343 11043431411_04_343
SELECT a,count(b) FROM t1 GROUP BY a ORDER BY a FOR UPDATE SKIP LOCKED;
a count(b) 033 042 051 071 112
SELECT d,a,b,c FROM t1 partition (p1,p9,p11,p17) ORDER BY d
FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
SELECT d,a,b,c FROM t1 ORDER BY d FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
SELECT d,a,b,c FROM t3 ORDER BY d FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
connection con1;
COMMIT;
connection con1;
BEGIN;
SELECT * FROM t1 WHERE a='01' LOCK IN SHARE MODE ;
a b c d e 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343
SELECT * FROM t3 FORCE INDEX(a) WHERE a='01' LOCK IN SHARE MODE ;
a b c d e 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343
connection con2;
BEGIN; SET SESSION innodb_lock_wait_timeout=1;
#
# SHARE ...
SELECT * FROM t1 LOCK IN SHARE MODE;
a b c d e 0303343703_03_343 0306343803_06_343 0307343903_07_343 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 11033431311_03_343 11043431411_04_343 0703343107_03_343
SELECT * FROM t1 LOCK IN SHARE MODE NOWAIT;
a b c d e 0303343703_03_343 0306343803_06_343 0307343903_07_343 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 11033431311_03_343 11043431411_04_343 0703343107_03_343
SELECT * FROM t1 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
a b c d e 0703343107_03_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 11033431311_03_343 11043431411_04_343 0104343201_04_343 0106343301_06_343 0107343401_07_343 0108343501_08_343 0109343601_09_343 0303343703_03_343 0306343803_06_343 0307343903_07_343
SELECT a,count(b) FROM t1 GROUP BY a ORDER BY a LOCK IN SHARE MODE SKIP LOCKED;
a count(b) 015 033 042 051 071 112
SELECT d,a,b,c FROM t1 partition (p1,p9,p11,p17) ORDER BY d
LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 20104343 30106343 40107343 50108343 60109343 70303343 80306343 90307343
SELECT d,a,b,c FROM t1 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 20104343 30106343 40107343 50108343 60109343 70303343 80306343 90307343
ANALYZE TABLE t3;
Table Op Msg_type Msg_text
test.t3 analyze status Engine-independent statistics collected
test.t3 analyze status OK
SELECT d,a,b,c FROM t3 ORDER BY d LOCK IN SHARE MODE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 20104343 30106343 40107343 50108343 60109343 70303343 80306343 90307343
explain SELECT d,a,b,c FROM t3 ORDER BY d
LOCK IN SHARE MODE SKIP LOCKED;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t3 index NULL PRIMARY 257 NULL 14
#
# UPDATE ...
SELECT * FROM t1 FOR UPDATE; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 FOR UPDATE NOWAIT; ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SELECT * FROM t1 ORDER BY a FOR UPDATE SKIP LOCKED;
a b c d e 0303343703_03_343 0306343803_06_343 0307343903_07_343 04033431004_03_343 04063431104_06_343 05033431205_03_343 0703343107_03_343 11033431311_03_343 11043431411_04_343
SELECT a,count(b) FROM t1 GROUP BY a ORDER BY a FOR UPDATE SKIP LOCKED;
a count(b) 033 042 051 071 112
SELECT d,a,b,c FROM t1 partition (p1,p9,p11,p17) ORDER BY d
FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
SELECT d,a,b,c FROM t1 ORDER BY d FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
SELECT d,a,b,c FROM t3 ORDER BY d FOR UPDATE SKIP LOCKED;
d a b c 10703343 100403343 110406343 120503343 131103343 141104343 70303343 80306343 90307343
connection default;
disconnect con1;
disconnect con2;
DROP TABLE t1, t2, t3;
DROP USER test@localhost;
DROP USER test2@localhost; set @@global.read_only= @start_read_only; set @@global.autocommit= @start_autocommit; set default_storage_engine= default;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.12 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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