37 lines
1.6 KiB
Plaintext
37 lines
1.6 KiB
Plaintext
|
|
====================================================================
|
|
Testing index for columns NAME
|
|
====================================================================
|
|
############ Explain for Query ####################################
|
|
explain select ENABLED
|
|
from performance_schema.setup_consumers
|
|
where 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 ENABLED
|
|
from performance_schema.setup_consumers
|
|
where NAME > "impossible";
|
|
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
|
|
1 SIMPLE setup_consumers NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
|
|
############ Explain for Query ####################################
|
|
explain select ENABLED
|
|
from performance_schema.setup_consumers
|
|
where NAME < "2";
|
|
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
|
|
1 SIMPLE setup_consumers NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
|
|
############ Explain for Query ####################################
|
|
explain select ENABLED
|
|
from performance_schema.setup_consumers
|
|
where NAME = "statements_digest";
|
|
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
|
|
1 SIMPLE setup_consumers NULL const PRIMARY PRIMARY 258 const # 100.00 NULL
|
|
############# Explain End #########################################
|
|
flush status;
|
|
select ENABLED
|
|
from performance_schema.setup_consumers
|
|
where NAME = "statements_digest";
|
|
ENABLED
|
|
#
|
|
OK: handler_read_key incremented
|