Key_reads

Overview

Shows the number of physical MyISAM index blocks read from disk and inserted into the MyISAM key cache.

USAGE

DETAILS

Scope

Global

Data Type

numeric

The Key_reads status variable shows the number of physical MyISAM index blocks read from disk and inserted into the MyISAM key cache.

For information about how to configure the key buffer size and compute the miss and write rates in the key cache, see key_buffer_size.

SYNONYMS

SCHEMA

PARAMETERS

SKYSQL

PRIVILEGES

EXAMPLES

Show Value with SHOW STATUS

SHOW GLOBAL STATUS statement can show the global value:

SHOW GLOBAL STATUS
   LIKE 'Key_reads';

Since this status variable is only global scope, SHOW STATUS and SHOW SESSION STATUS also show the global value.

Information Schema

The information_schema.GLOBAL_STATUS table can be queried to obtain the global value:

SELECT *
FROM information_schema.GLOBAL_STATUS
WHERE VARIABLE_NAME LIKE 'Key_reads';

This status variable is only global scope, so the information_schema.SESSION_STATUS table can also be queried to obtain the global value:

SELECT *
FROM information_schema.SESSION_STATUS
WHERE VARIABLE_NAME LIKE 'Key_reads';

ERROR HANDLING

FEATURE INTERACTION

RESPONSES

DIAGNOSIS

ISO 9075:2016

CHANGE HISTORY

Release Series

History

23.08 Enterprise

  • Present starting in MariaDB Enterprise Server 23.08.0.

23.07 Enterprise

  • Present starting in MariaDB Enterprise Server 23.07.0.

10.6 Enterprise

  • Present starting in MariaDB Enterprise Server 10.6.4-1.

10.6 Community

  • Present starting in MariaDB Community Server 10.6.0.

10.5 Enterprise

  • Present starting in MariaDB Enterprise Server 10.5.3-1.

10.5 Community

  • Present starting in MariaDB Community Server 10.5.0.

10.4 Enterprise

  • Present starting in MariaDB Enterprise Server 10.4.6-1.

10.4 Community

  • Present starting in MariaDB Community Server 10.4.0.

10.3 Enterprise

  • Present starting in MariaDB Enterprise Server 10.3.16-1.

10.3 Community

  • Present starting in MariaDB Community Server 10.3.0.

10.2 Enterprise

  • Present starting in MariaDB Enterprise Server 10.2.25-1.

10.2 Community

  • Present starting in MariaDB Community Server 10.2.0.

Release Series

History

23.08 Enterprise

  • Present starting in MariaDB Enterprise Server 23.08.0.

23.07 Enterprise

  • Present starting in MariaDB Enterprise Server 23.07.0.

10.6 Enterprise

  • Present starting in MariaDB Enterprise Server 10.6.4-1.

10.5 Enterprise

  • Present starting in MariaDB Enterprise Server 10.5.3-1.

10.4 Enterprise

  • Present starting in MariaDB Enterprise Server 10.4.6-1.

EXTERNAL REFERENCES