Possible to select individual values using SHOW STATUS in MySQL?
Is it possible to write a query that will return only the value of a variable returned by MySQL's SHOW STATUS? Ideally I want something li开发者_JS百科ke:
SELECT `Value` FROM (SHOW STATUS LIKE 'Com_delete')
or something similar.
Is this possible?
If you are using MySQL 5.1 or above, you should be able to get that data from INFORMATION_SCHEMA
like this for global status:
select VARIABLE_VALUE
from information_schema.GLOBAL_STATUS
where VARIABLE_NAME = 'Com_delete';
Or if you want the session status instead:
select VARIABLE_VALUE
from information_schema.SESSION_STATUS
where VARIABLE_NAME = 'Com_delete';
The default for SHOW STATUS
is SESSION
status, so the latter query would work as a replacement for that.
Complementing Ike Walker answer, INFORMATION_SCHEMA is deprecated on MySQL 5.7.6, as the Performance Schema tables are intended to replace the INFORMATION_SCHEMA tables.
So, by querying the INFORMATION_SCHEMA you may get an error like this:
The 'INFORMATION_SCHEMA.SESSION_STATUS' feature is disabled; see the documentation for 'show_compatibility_56'
According to this, you can set show_compatibility_56
to ON
to enable backwards compatibility and keep using 5.6 syntax, or enable the PERFORMANCE_SCHEMA and query the new tables:
performance_schema.global_variables
performance_schema.session_variables
performance_schema.global_status
performance_schema.session_status
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