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drop table if exists test.no_index_tab;
drop table if exists test.index_tab;
drop table if exists test.marker;
create table test.marker(a int);
update performance_schema.setup_consumers set enabled='NO';
update performance_schema.setup_instruments set enabled='NO';
update performance_schema.setup_instruments set enabled='YES'
where name like "wait/io/table/%";
truncate table performance_schema.events_waits_history_long;
flush global status;
flush tables;
create table test.no_index_tab
( a int, b char(30) default 'Default') engine = MyISAM;
create table test.index_tab
( a int, b char(30) default 'Default', unique key uidx(a)) engine = MyISAM;
show create table test.no_index_tab;
Table Create Table
no_index_tab CREATE TABLE `no_index_tab` (
`a` int(11) DEFAULT NULL,
`b` char(30) DEFAULT 'Default'
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
show create table test.index_tab;
Table Create Table
index_tab CREATE TABLE `index_tab` (
`a` int(11) DEFAULT NULL,
`b` char(30) DEFAULT 'Default',
UNIQUE KEY `uidx` (`a`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
# Printing of 100 inserts per table is suppressed
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'no_index_tab';
SUM(NUMBER_OF_BYTES)
100
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'index_tab';
SUM(NUMBER_OF_BYTES)
100
select count(*) from test.no_index_tab;
count(*)
100
select count(*) from test.index_tab;
count(*)
100
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
select avg(a) from test.no_index_tab;
avg(a)
50.5000
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'no_index_tab';
SUM(NUMBER_OF_BYTES)
100
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
select avg(a) from test.index_tab;
avg(a)
50.5000
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'index_tab';
SUM(NUMBER_OF_BYTES)
100
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
select 1 as my_column from test.no_index_tab where a = 50;
my_column
1
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'no_index_tab';
SUM(NUMBER_OF_BYTES)
100
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
select 1 as my_column from test.index_tab where a = 50;
my_column
1
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'index_tab';
SUM(NUMBER_OF_BYTES)
1
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
delete from test.no_index_tab where a = 51;
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'no_index_tab';
SUM(NUMBER_OF_BYTES)
102
truncate table performance_schema.events_waits_history_long;
update performance_schema.setup_consumers set enabled='YES';
delete from test.index_tab where a = 51;
update performance_schema.setup_consumers set enabled='NO';
select SUM(NUMBER_OF_BYTES)
from performance_schema.events_waits_history_long
where event_name like 'wait/io/table/%'
and object_schema = 'test'
and object_name = 'index_tab';
SUM(NUMBER_OF_BYTES)
2
show global status like 'performance_schema_%';
Variable_name Value
Performance_schema_accounts_lost 0
Performance_schema_cond_classes_lost 0
Performance_schema_cond_instances_lost 0
Performance_schema_digest_lost 0
Performance_schema_file_classes_lost 0
Performance_schema_file_handles_lost 0
Performance_schema_file_instances_lost 0
Performance_schema_hosts_lost 0
Performance_schema_index_stat_lost 0
Performance_schema_locker_lost 0
Performance_schema_memory_classes_lost 0
Performance_schema_metadata_lock_lost 0
Performance_schema_mutex_classes_lost 0
Performance_schema_mutex_instances_lost 0
Performance_schema_nested_statement_lost 0
Performance_schema_prepared_statements_lost 0
Performance_schema_program_lost 0
Performance_schema_rwlock_classes_lost 0
Performance_schema_rwlock_instances_lost 0
Performance_schema_session_connect_attrs_lost 0
Performance_schema_socket_classes_lost 0
Performance_schema_socket_instances_lost 0
Performance_schema_stage_classes_lost 0
Performance_schema_statement_classes_lost 0
Performance_schema_table_handles_lost 0
Performance_schema_table_instances_lost 0
Performance_schema_table_lock_stat_lost 0
Performance_schema_thread_classes_lost 0
Performance_schema_thread_instances_lost 0
Performance_schema_users_lost 0
drop table test.no_index_tab;
drop table test.index_tab;
update performance_schema.setup_consumers set enabled='NO';
truncate performance_schema.events_waits_history_long;
drop table test.marker;
flush global status;
update performance_schema.setup_instruments set enabled='YES';
update performance_schema.setup_consumers set enabled='YES';
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