include/master-slave.inc
[connection master]
include/stop_slave.inc
RESET SLAVE ALL;
include/start_slave.inc

====================================================================
Testing index for columns CHANNEL_NAME
====================================================================
############ Explain for Query ####################################
explain select REMAINING_DELAY 
from performance_schema.replication_applier_status 
where CHANNEL_NAME = "impossible";
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	no matching row in const table
############ Explain for Query ####################################
explain select REMAINING_DELAY
from performance_schema.replication_applier_status
where CHANNEL_NAME > "impossible";
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	replication_applier_status	NULL	ALL	PRIMARY	NULL	NULL	NULL	#	33.33	Using where
############ Explain for Query ####################################
explain select REMAINING_DELAY
from performance_schema.replication_applier_status
where CHANNEL_NAME < "2";
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	replication_applier_status	NULL	ALL	PRIMARY	NULL	NULL	NULL	#	33.33	Using where
############ Explain for Query ####################################
explain select REMAINING_DELAY
from performance_schema.replication_applier_status
where CHANNEL_NAME = "channel_1";
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	replication_applier_status	NULL	const	PRIMARY	PRIMARY	256	const	#	100.00	NULL
############# Explain End #########################################
flush status;
select REMAINING_DELAY
from performance_schema.replication_applier_status
where CHANNEL_NAME = "channel_1";
REMAINING_DELAY
#
OK: handler_read_key incremented
include/stop_slave.inc
RESET SLAVE ALL;
include/start_slave.inc
include/rpl_end.inc