MariaDB starting with 10.1.x

The QUERY_CACHE_QUERIES table will be introduced in a future version of MariaDB. See MDEV-4682

Description

The QUERY_CACHE_QUERIES table will be introduced as part of a future change to the QUERY_CACHE_INFO plugin, and allows you to see the contents of the query cache. It replaces the QUERY_CACHE_INFO table.

The table is not a standard Information Schema table, and is a MariaDB extension.

It contains the following columns:

ColumnDescription
QUERY_CACHE_IDcache entry id (only for qc_info plugin, internally server use a hash table)
STATEMENT_SCHEMAschema used when query was included
STATEMENT_TEXTquery text
RESULT_FOUND_ROWS
QUERY_ROWS
SELECT_ROWS_READ
QUERY_HITSQuery cache hits in this entry
QUERY_HITS_PERIOD_LOWperiod between hits that is faster than executing the query without query cache (a good hit rate have many hits here), removing this query entry will consume more time than returning value from query cache
QUERY_HITS_PERIOD_HIGHperiod between hits that is slower than executing the query without query cache and is 10 times faster than executing the query without query cache, but isn't slow than 1 second, removing this query will not give problems to users but will increase disk i/o - in future version "10 times" should be replaced to number of competitors trying to include the same query +1
QUERY_HITS_PERIOD_OUTLIERSperiod between hits that is higher than is not HIGH or LOW
QUERY_HITS_TOTAL_TIME_UStotal time expend with query cache
QUERY_HITS_MEAN_PERIOD_USmean query cache period between hits
QUERY_HITS_MEAN_PERIOD_LOW_USmean query cache period between LOW hits
QUERY_HITS_MEAN_PERIOD_HIGH_USmean query cache period between HIGH hits
QUERY_INSERT_TIMEtime that query was inserted at query cache
QUERY_LAST_HIT_TIMElast time the query was hit at query cache
SELECT_EXPEND_TIME_USquery expend time
SELECT_LOCK_TIME_USquery lock expend time
TABLES_TYPEinternal use, possible values: NON TRANSACT, NO CACHE, ASK TRANSACT, TRANSACT, "UNKNOWN %u" where %u is a value of query_cache_query->tables_type()
RESULT_LENGTHlength of result
RESULT_BLOCKS_COUNTnumber of result blocks
RESULT_BLOCKS_SIZEsize of result blocks
RESULT_BLOCKS_SIZE_USEDsize of used blocks
FLAGS_CLIENT_LONG_FLAGconnection flag (part of query cache hash)
FLAGS_CLIENT_PROTOCOL_41connection flag (part of query cache hash)
FLAGS_PROTOCOL_TYPEconnection flag (part of query cache hash)
FLAGS_MORE_RESULTS_EXISTSconnection flag (part of query cache hash)
FLAGS_IN_TRANSconnection flag (part of query cache hash)
FLAGS_AUTOCOMMITconnection flag (part of query cache hash)
FLAGS_PKT_NRconnection flag (part of query cache hash)
FLAGS_CHARACTER_SET_CLIENTconnection flag (part of query cache hash)
FLAGS_CHARACTER_SET_RESULTSconnection flag (part of query cache hash)
FLAGS_COLLATION_CONNECTIONconnection flag (part of query cache hash)
FLAGS_LIMITconnection flag (part of query cache hash)
FLAGS_TIME_ZONEconnection flag (part of query cache hash)
FLAGS_SQL_MODEconnection flag (part of query cache hash)
FLAGS_MAX_SORT_LENGTHconnection flag (part of query cache hash)
FLAGS_GROUP_CONCAT_MAX_LENconnection flag (part of query cache hash)
FLAGS_DIV_PRECISION_INCREMENTconnection flag (part of query cache hash)
FLAGS_DEFAULT_WEEK_FORMATconnection flag (part of query cache hash)
FLAGS_LC_TIME_NAMESconnection flag (part of query cache hash)

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