---- establish connection con1 (root) ----
---- switch to connection default ----
set @initial_query_cache_size = @@global.query_cache_size;
set @@global.query_cache_size=100000;
flush status;
drop table if exists t1;
create table t1(c1 int);
insert into t1 values(1),(10),(100);
prepare stmt1 from "select * from t1 where c1=10";
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	0
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	0
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	1
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	2
prepare stmt2 from "select * from t1 where c1=10";
execute stmt2;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	3
execute stmt2;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	4
execute stmt2;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	5
---- switch to connection con1 ----
prepare stmt3 from "select * from t1 where c1=10";
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	6
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	7
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	8
---- switch to connection default ----
prepare stmt10 from "SELECT * FROM t1 WHERE c1 = 100";
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	8
execute stmt10;
c1
100
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	8
execute stmt10;
c1
100
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	9
SELECT * FROM t1 WHERE c1 = 100;
c1
100
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	10
---- switch to connection con1 ----
SELECT * FROM t1 WHERE c1 = 100;
c1
100
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	11
---- switch to connection default ----
prepare stmt11 from "SELECT * FROM t1 WHERE c1 = 1";
---- switch to connection con1 ----
prepare stmt12 from "SELECT * FROM t1 WHERE c1 = 1";
---- switch to connection default ----
SELECT * FROM t1 WHERE c1 = 1;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	11
SELECT * FROM t1 WHERE c1 = 1;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	12
execute stmt11;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	13
---- switch to connection con1 ----
execute stmt12;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	14
---- switch to connection default ----
prepare stmt1 from "select * from t1 where c1=?";
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	14
set @a=1;
execute stmt1 using @a;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	14
execute stmt1 using @a;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	15
---- switch to connection con1 ----
set @a=1;
prepare stmt4 from "select * from t1 where c1=?";
execute stmt4 using @a;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
prepare stmt4 from "select @a from t1 where c1=?";
execute stmt4 using @a;
@a
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt4 using @a;
@a
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
---- switch to connection default ----
prepare stmt1 from "select * from t1 where c1=10";
set global query_cache_size=0;
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
---- switch to connection con1 ----
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
---- switch to connection default ----
set global query_cache_size=100000;
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	16
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	17
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	18
---- switch to connection con1 ----
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	19
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	20
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
---- switch to connection default ----
set global query_cache_size=0;
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
---- switch to connection con1 ----
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
---- switch to connection default ----
set global query_cache_size=0;
prepare stmt1 from "select * from t1 where c1=10";
---- switch to connection con1 ----
prepare stmt3 from "select * from t1 where c1=10";
---- switch to connection default ----
set global query_cache_size=100000;
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt1;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
---- switch to connection con1 ----
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
execute stmt3;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
---- switch to connection default ----
set global query_cache_size=0;
prepare stmt1 from "select * from t1 where c1=?";
set global query_cache_size=100000;
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
set @a=1;
execute stmt1 using @a;
c1
1
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
set @a=100;
execute stmt1 using @a;
c1
100
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
set @a=10;
execute stmt1 using @a;
c1
10
show status like 'Qcache_hits';
Variable_name	Value
Qcache_hits	21
drop table t1;
---- disconnect connection con1 ----
set @@global.query_cache_size=@initial_query_cache_size;
flush status;