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SET global query_cache_type=ON;
SET local query_cache_type=ON;
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
drop table if exists t1,t2,t3;
set @save_query_cache_size = @@global.query_cache_size;
set GLOBAL query_cache_size = 1355776;
flush status;
set autocommit=0;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
select * from t1;
a
1
2
3
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
drop table t1;
commit;
set autocommit=1;
begin;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
select * from t1;
a
1
2
3
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
drop table t1;
commit;
create table t1 (a int not null);
create table t2 (a int not null);
create table t3 (a int not null);
insert into t1 values (1),(2);
insert into t2 values (1),(2);
insert into t3 values (1),(2);
select * from t1;
a
1
2
select * from t2;
a
1
2
select * from t3;
a
1
2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 3
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 0
begin;
select * from t1;
a
1
2
select * from t2;
a
1
2
select * from t3;
a
1
2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 6
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 0
insert into t1 values (3);
insert into t2 values (3);
insert into t1 values (4);
select * from t1;
a
1
2
3
4
select * from t2;
a
1
2
3
select * from t3;
a
1
2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 1
commit;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
drop table t3,t2,t1;
CREATE TABLE t1 (id int(11) NOT NULL auto_increment, PRIMARY KEY (id));
select count(*) from t1;
count(*)
0
insert into t1 (id) values (0);
select count(*) from t1;
count(*)
1
drop table t1;
CREATE TABLE t1 ( id int(10) NOT NULL auto_increment, a varchar(25) default NULL, PRIMARY KEY (id), UNIQUE KEY a (a));
CREATE TABLE t2 ( id int(10) NOT NULL auto_increment, b varchar(25) default NULL, PRIMARY KEY (id), UNIQUE KEY b (b));
CREATE TABLE t3 ( id int(10) NOT NULL auto_increment, t1_id int(10) NOT NULL default '0', t2_id int(10) NOT NULL default '0', state int(11) default NULL, PRIMARY KEY (id), UNIQUE KEY t1_id (t1_id,t2_id), KEY t2_id (t2_id,t1_id), CONSTRAINT `t3_ibfk_1` FOREIGN KEY (`t1_id`) REFERENCES `t1` (`id`), CONSTRAINT `t3_ibfk_2` FOREIGN KEY (`t2_id`) REFERENCES `t2` (`id`));
INSERT INTO t1 VALUES (1,'me');
INSERT INTO t2 VALUES (1,'you');
INSERT INTO t3 VALUES (2,1,1,2);
delete from t3 where t1_id = 1 and t2_id = 1;
select t1.* from t1, t2, t3 where t3.state & 1 = 0 and t3.t1_id = t1.id and t3.t2_id = t2.id and t1.id = 1 order by t1.a asc;
id a
begin;
insert into t3 VALUES ( NULL, 1, 1, 2 );
insert into t3 VALUES ( NULL, 1, 1, 2 );
ERROR 23000: Duplicate entry '1-1' for key 't1_id'
commit;
select t1.* from t1, t2, t3 where t3.state & 1 = 0 and t3.t1_id = t1.id and t3.t2_id = t2.id and t1.id = 1 order by t1.a asc;
id a
1 me
drop table t3,t2,t1;
connect connection1,localhost,root,,;
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
SET @@autocommit=1;
connection default;
SHOW VARIABLES LIKE 'have_query_cache';
Variable_name Value
have_query_cache YES
SET GLOBAL query_cache_size = 204800;
flush status;
SET @@autocommit=1;
SET SESSION DEFAULT_STORAGE_ENGINE = InnoDB;
CREATE TABLE t2 (s1 int, s2 varchar(1000), key(s1));
INSERT INTO t2 VALUES (1,repeat('a',10)),(2,repeat('a',10)),(3,repeat('a',10)),(4,repeat('a',10));
COMMIT;
START TRANSACTION;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
0
UPDATE t2 SET s2 = 'w' WHERE s1 = 3;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
connection connection1;
START TRANSACTION;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
0
INSERT INTO t2 VALUES (5,'w');
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
1
COMMIT;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
connection default;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
1
COMMIT;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
connection connection1;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
START TRANSACTION;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
INSERT INTO t2 VALUES (6,'w');
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
3
connection default;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
START TRANSACTION;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
DELETE from t2 WHERE s1=3;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
1
COMMIT;
connection connection1;
COMMIT;
SELECT sql_cache count(*) FROM t2 WHERE s2 = 'w';
count(*)
2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 1
disconnect connection1;
connection default;
set @@global.query_cache_size = @save_query_cache_size;
drop table t2;
SET global query_cache_type=default;
CREATE TABLE t1 (a INT) ENGINE=InnoDB;
BEGIN;
INSERT INTO t1 VALUES(1);
ROLLBACK WORK AND CHAIN NO RELEASE;
SELECT a FROM t1;
a
ROLLBACK WORK AND CHAIN NO RELEASE;
SELECT a FROM t1;
a
ROLLBACK;
DROP TABLE t1;
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