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|
flush query cache;
flush query cache;
reset query cache;
flush status;
drop database if exists mysqltest;
drop table if exists t1,t2,t3,t11,t21, mysqltest.t1;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
select * from t1;
a
1
2
3
select * from t1;
a
1
2
3
select sql_no_cache * from t1;
a
1
2
3
select length(now()) from t1;
length(now())
19
19
19
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
show status like "Qcache_inserts";
Variable_name Value
Qcache_inserts 1
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 1
drop table t1;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
create table t2 (a int not null);
insert into t2 values (4),(5),(6);
create table t3 (a int not null) type=MERGE UNION=(t1,t2) INSERT_METHOD=FIRST;
select * from t3;
a
1
2
3
4
5
6
select * from t3;
a
1
2
3
4
5
6
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 2
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
insert into t2 values (7);
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select * from t1;
a
1
2
3
select * from t1;
a
1
2
3
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 3
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
insert into t3 values (8);
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select * from t3;
a
1
2
3
8
4
5
6
7
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
update t2 set a=9 where a=7;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select * from t1;
a
1
2
3
8
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
update t3 set a=10 where a=1;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select * from t3;
a
10
2
3
8
4
5
6
9
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
delete from t2 where a=9;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select * from t1;
a
10
2
3
8
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
delete from t3 where a=10;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
drop table t1, t2, t3;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
create table t2 (a int not null);
insert into t2 values (1),(2),(3);
select * from t1;
a
1
2
3
select * from t2;
a
1
2
3
insert into t1 values (4);
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 2
flush query cache;
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
drop table t1, t2;
create table t1 (a text not null);
create table t11 (a text not null);
create table t2 (a text not null);
create table t21 (a text not null);
create table t3 (a text not null);
insert into t1 values("1111111111111111111111111111111111111111111111111111");
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t11 select * from t1;
insert into t21 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t3 select * from t1;
insert into t3 select * from t2;
insert into t3 select * from t1;
select * from t11;
select * from t21;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 7
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
insert into t11 values("");
select * from t3;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 8
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
flush query cache;
show status like "Qcache_total_blocks";
Variable_name Value
Qcache_total_blocks 7
show status like "Qcache_free_blocks";
Variable_name Value
Qcache_free_blocks 1
drop table t1, t2, t3, t11, t21;
set query_cache_type=demand;
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
select sql_cache * from t1;
a
1
2
3
set query_cache_type=2;
select sql_cache * from t1;
a
1
2
3
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 4
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
set query_cache_type=on;
reset query cache;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
select sql_no_cache * from t1;
a
1
2
3
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
drop table t1;
create table t1 (a text not null);
select CONNECTION_ID() from t1;
CONNECTION_ID()
select FOUND_ROWS();
FOUND_ROWS()
0
select NOW() from t1;
NOW()
select CURDATE() from t1;
CURDATE()
select CURTIME() from t1;
CURTIME()
select DATABASE() from t1;
DATABASE()
select ENCRYPT("test") from t1;
ENCRYPT("test")
select LAST_INSERT_ID() from t1;
last_insert_id()
select RAND() from t1;
RAND()
select UNIX_TIMESTAMP() from t1;
UNIX_TIMESTAMP()
select USER() from t1;
USER()
select benchmark(1,1) from t1;
benchmark(1,1)
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
create table t2 (a text not null);
insert into t1 values("1111111111111111111111111111111111111111111111111111");
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 4
show status like "Qcache_lowmem_prunes";
Variable_name Value
Qcache_lowmem_prunes 0
select a as a1, a as a2 from t1;
select a as a2, a as a3 from t1;
select a as a3, a as a4 from t1;
select a as a1, a as a2 from t1;
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 4
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
show status like "Qcache_lowmem_prunes";
Variable_name Value
Qcache_lowmem_prunes 2
reset query cache;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
insert into t2 select * from t1;
insert into t1 select * from t2;
select * from t1;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
drop table t1,t2;
create database if not exists mysqltest;
create table mysqltest.t1 (i int not null auto_increment, a int, primary key (i));
insert into mysqltest.t1 (a) values (1);
select * from mysqltest.t1 where i is null;
i a
1 1
select * from mysqltest.t1;
i a
1 1
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
drop database mysqltest;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
create table t1 (a char(1) not null);
insert into t1 values("á");
select * from t1;
a
á
set CHARACTER SET cp1251_koi8;
select * from t1;
a
À
set CHARACTER SET DEFAULT;
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 4
drop table t1;
create database if not exists mysqltest;
create table mysqltest.t1 (i int not null);
create table t1 (i int not null);
insert into mysqltest.t1 (i) values (1);
insert into t1 (i) values (2);
select * from t1;
i
2
use mysqltest;
select * from t1;
i
1
select * from t1;
i
1
use test;
select * from t1;
i
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 6
drop database mysqltest;
drop table t1;
create table t1 (i int not null);
insert into t1 (i) values (1),(2),(3),(4);
select SQL_CALC_FOUND_ROWS * from t1 limit 2;
i
1
2
select FOUND_ROWS();
FOUND_ROWS()
4
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 6
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
select * from t1 where i=1;
i
1
select FOUND_ROWS();
FOUND_ROWS()
1
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 6
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
select SQL_CALC_FOUND_ROWS * from t1 limit 2;
i
1
2
select FOUND_ROWS();
FOUND_ROWS()
4
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 7
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
select * from t1 where i=1;
i
1
select FOUND_ROWS();
FOUND_ROWS()
1
show status like "Qcache_hits";
Variable_name Value
Qcache_hits 8
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
drop table t1;
flush query cache;
reset query cache;
create table t1 (a int not null);
insert into t1 values (1),(2),(3);
select * from t1;
a
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
insert delayed into t1 values (4);
select a from t1;
a
1
2
3
4
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
drop table t1;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
set GLOBAL query_cache_size=1000;
show global variables like "query_cache_size";
Variable_name Value
query_cache_size 0
set GLOBAL query_cache_size=1100;
set GLOBAL query_cache_size=1200;
set GLOBAL query_cache_size=1300;
set GLOBAL query_cache_size=1400;
set GLOBAL query_cache_size=1500;
set GLOBAL query_cache_size=1600;
set GLOBAL query_cache_size=1700;
set GLOBAL query_cache_size=1800;
set GLOBAL query_cache_size=1900;
show global variables like "query_cache_size";
Variable_name Value
query_cache_size 1024
set GLOBAL query_cache_size=1048576;
create table t1 (i int not null);
create table t2 (i int not null);
select * from t1;
i
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 1
create temporary table t3 (i int not null);
select * from t2;
i
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
select * from t3;
i
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 2
update t1 set i=(select distinct 1 from (select * from t2) a);
drop table t1, t2, t3;
use mysql;
select * from db;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
use test;
select * from mysql.db;
show status like "Qcache_queries_in_cache";
Variable_name Value
Qcache_queries_in_cache 0
|
