Information Schema QUERY_CACHE_INFO Table

The Information Schema QUERY_CACHE_INFO table shows all queries currently stored in the query cache, aiding in cache performance analysis.

Description

This table is not a standard Information Schema table, but a MariaDB extension.

The QUERY_CACHE_INFO table is created by the QUERY_CACHE_INFO plugin, and allows you to see the contents of the query cache. It creates a table in the information_schema database that shows all queries that are in the cache. You must have the PROCESS privilege (see GRANT) to use this table.

It contains the following columns:

Column	Description
STATEMENT_SCHEMA	Database used when query was included
STATEMENT_TEXT	Query text
RESULT_BLOCKS_COUNT	Number of result blocks
RESULT_BLOCKS_SIZE	Size in bytes of result blocks
RESULT_BLOCKS_SIZE_USED	Size in bytes of used blocks
LIMIT
MAX_SORT_LENGTH
GROUP_CONCAT_MAX_LENGTH
CHARACTER_SET_CLIENT
CHARACTER_SET_RESULT
COLLATION
TIMEZONE
DEFAULT_WEEK_FORMAT
DIV_PRECISION_INCREMENT
SQL_MODE
LC_TIME_NAMES
CLIENT_LONG_FLAG
CLIENT_PROTOCOL_41
PROTOCOL_TYPE
MORE_RESULTS_EXISTS
IN_TRANS
AUTOCOMMIT
PACKET_NUMBER
HITS	Incremented each time the query cache is hit.

For example:

SELECT * FROM information_schema.QUERY_CACHE_INFO;
+------------------+-----------------+---------------------+--------------------+-------------------------+
| STATEMENT_SCHEMA | STATEMENT_TEXT  | RESULT_BLOCKS_COUNT | RESULT_BLOCKS_SIZE | RESULT_BLOCKS_SIZE_USED |
+------------------+-----------------+---------------------+--------------------+-------------------------+
...
| test             | SELECT * FROM a |                   1 |                512 |                     143 |
| test             | select * FROM a |                   1 |                512 |                     143 |
...
+------------------+-----------------+---------------------+--------------------+-------------------------

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