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include/master-slave.inc
[connection master]
include/stop_slave.inc
RESET SLAVE ALL;
include/start_slave.inc
select THREAD_ID from performance_schema.replication_connection_status
where CHANNEL_NAME = "channel_1"
into @tid;
====================================================================
Testing index for columns CHANNEL_NAME
====================================================================
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_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 SERVICE_STATE
from performance_schema.replication_connection_status
where CHANNEL_NAME > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where CHANNEL_NAME < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where CHANNEL_NAME = "channel_1";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL const PRIMARY PRIMARY 256 const # 100.00 NULL
############# Explain End #########################################
flush status;
select SERVICE_STATE
from performance_schema.replication_connection_status
where CHANNEL_NAME = "channel_1";
SERVICE_STATE
#
OK: handler_read_key incremented
====================================================================
Testing index for columns THREAD_ID
====================================================================
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where THREAD_ID = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ref THREAD_ID THREAD_ID 9 const # 100.00 Using where
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where THREAD_ID > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ALL THREAD_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where THREAD_ID < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ALL THREAD_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select SERVICE_STATE
from performance_schema.replication_connection_status
where THREAD_ID = @tid;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE replication_connection_status NULL ref THREAD_ID THREAD_ID 9 const # 100.00 NULL
############# Explain End #########################################
flush status;
select SERVICE_STATE
from performance_schema.replication_connection_status
where THREAD_ID = @tid;
SERVICE_STATE
#
OK: handler_read_key incremented
include/stop_slave.inc
RESET SLAVE ALL;
Warnings:
Warning 1287 'RESET SLAVE' is deprecated and will be removed in a future release. Please use RESET REPLICA instead
include/start_slave.inc
include/rpl_end.inc
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