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select OBJECT_INSTANCE_BEGIN, THREAD_ID, SOCKET_ID, IP, PORT
from performance_schema.socket_instances
limit 1
into @oib, @tid, @sid, @ip, @port;
====================================================================
Testing index for columns OBJECT_INSTANCE_BEGIN
====================================================================
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where OBJECT_INSTANCE_BEGIN = "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 COUNT(*)
from performance_schema.socket_instances
where OBJECT_INSTANCE_BEGIN > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where OBJECT_INSTANCE_BEGIN < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where OBJECT_INSTANCE_BEGIN = @oib;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL const PRIMARY PRIMARY 8 const # 100.00 NULL
############# Explain End #########################################
flush status;
select COUNT(*)
from performance_schema.socket_instances
where OBJECT_INSTANCE_BEGIN = @oib;
COUNT(*)
#
OK: handler_read_key incremented
====================================================================
Testing index for columns THREAD_ID
====================================================================
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where THREAD_ID = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref THREAD_ID THREAD_ID 9 const # 100.00 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where THREAD_ID > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL THREAD_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where THREAD_ID < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL THREAD_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where THREAD_ID = @tid;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref THREAD_ID THREAD_ID 9 const # 100.00 NULL
############# Explain End #########################################
flush status;
select COUNT(*)
from performance_schema.socket_instances
where THREAD_ID = @tid;
COUNT(*)
#
OK: handler_read_key incremented
====================================================================
Testing index for columns SOCKET_ID
====================================================================
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where SOCKET_ID = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref SOCKET_ID SOCKET_ID 4 const # 100.00 NULL
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where SOCKET_ID > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL SOCKET_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where SOCKET_ID < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL SOCKET_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where SOCKET_ID = @sid;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref SOCKET_ID SOCKET_ID 4 const # 100.00 NULL
############# Explain End #########################################
flush status;
select COUNT(*)
from performance_schema.socket_instances
where SOCKET_ID = @sid;
COUNT(*)
#
OK: handler_read_key incremented
====================================================================
Testing index for columns IP, PORT
====================================================================
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 258 const # 100.00 NULL
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL IP NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ALL IP NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = @ip;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 258 const # 100.00 NULL
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = "impossible"
and PORT = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 262 const,const # 100.00 NULL
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = @ip
and PORT = "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 262 const,const # 100.00 NULL
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = @ip
and PORT > "impossible";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 258 const # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = @ip
and PORT < "2";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 258 const # 33.33 Using where
############ Explain for Query ####################################
explain select COUNT(*)
from performance_schema.socket_instances
where IP = @ip
and PORT = @port;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE socket_instances NULL ref IP IP 262 const,const # 100.00 NULL
############# Explain End #########################################
flush status;
select COUNT(*)
from performance_schema.socket_instances
where IP = @ip
and PORT = @port;
COUNT(*)
#
OK: handler_read_key incremented
|
