set @save_query_cache_size=@@query_cache_size;
drop table if exists t1;
create table t1 (a int not null);
insert into t1 values (1), (2), (3);
SET GLOBAL query_cache_size=1355776;
flush query cache;
reset query cache;
flush status;
select * from t1;
a
1
2
3
show global status like "Qcache_queries_in_cache";
Variable_name	Value
Qcache_queries_in_cache	1
show global status like "Qcache_inserts";
Variable_name	Value
Qcache_inserts	1
show global status like "Qcache_hits";
Variable_name	Value
Qcache_hits	0
select * from t1;
a
1
2
3
show global status like "Qcache_queries_in_cache";
Variable_name	Value
Qcache_queries_in_cache	1
show global status like "Qcache_inserts";
Variable_name	Value
Qcache_inserts	1
show global status like "Qcache_hits";
Variable_name	Value
Qcache_hits	1
select spins from performance_schema.events_waits_current order by event_name limit 1;
spins
NULL
select * from performance_schema.setup_timers where name='wait';
NAME	TIMER_NAME
wait	{CYCLE_OR_NANOSECOND}
Warnings:
Warning	1681	'performance_schema.setup_timers' is deprecated and will be removed in a future release
show global status like "Qcache_queries_in_cache";
Variable_name	Value
Qcache_queries_in_cache	1
show global status like "Qcache_inserts";
Variable_name	Value
Qcache_inserts	1
show global status like "Qcache_hits";
Variable_name	Value
Qcache_hits	1
select spins from performance_schema.events_waits_current order by event_name limit 1;
spins
NULL
select * from performance_schema.setup_timers where name='wait';
NAME	TIMER_NAME
wait	{CYCLE_OR_NANOSECOND}
Warnings:
Warning	1681	'performance_schema.setup_timers' is deprecated and will be removed in a future release
show global status like "Qcache_queries_in_cache";
Variable_name	Value
Qcache_queries_in_cache	1
show global status like "Qcache_inserts";
Variable_name	Value
Qcache_inserts	1
show global status like "Qcache_hits";
Variable_name	Value
Qcache_hits	1
SET GLOBAL query_cache_size=@save_query_cache_size;
drop table t1;
flush status;