Manual:Querycache table

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MediaWiki database layoutManual:Database layout

querycache table

The querycache table is used for caching expensive grouped queries.

Fields

qc_type

A key name, generally the base name of the special page.

qc_value

Some sort of stored value. Sizes, counts...

qc_namespace

Target namespace. Used in conjunction with gc_title.

qc_title

Target title. Used in conjunction with gc_namespace.

Versions

MediaWiki versions:

1.19 – 1.20

mysql> describe querycache;
+--------------+------------------+------+-----+---------+-------+
| Field        | Type             | Null | Key | Default | Extra |
+--------------+------------------+------+-----+---------+-------+
| qc_type      | varbinary(32)    | NO   | MUL | NULL    |       |
| qc_value     | int(10) unsigned | NO   |     | 0       |       |
| qc_namespace | int(11)          | NO   |     | 0       |       |
| qc_title     | varbinary(255)   | NO   |     |         |       |
+--------------+------------------+------+-----+---------+-------+

MediaWiki version:

1.18

describe querycache;

+--------------+----------------------+------+-----+---------+-------+
| Field        | Type                 | Null | Key | Default | Extra |
+--------------+----------------------+------+-----+---------+-------+
| qc_type      | varbinary(32)        |      | MUL |         |       |
| qc_value     | int(10) unsigned     |      |     | 0       |       |
| qc_namespace | tinyint(11) unsigned |      |     | 0       |       |
| qc_title     | varchar(255)         |      |     |         |       |
+--------------+----------------------+------+-----+---------+-------+

describe querycache; in MediaWiki 1.8 gives the following:

MediaWiki version:

1.8

+--------------+-----------------+------+-----+---------+-------+
| Field        | Type            | Null | Key | Default | Extra |
+--------------+-----------------+------+-----+---------+-------+
| qc_type      | char(32)        | NO   | MUL | NULL    |       |
| qc_value     | int(5) unsigned | NO   |     | 0       |       |
| qc_namespace | int(11)         | NO   |     | 0       |       |
| qc_title     | char(255)       | NO   |     | NULL    |       |
+--------------+-----------------+------+-----+---------+-------+

MediaWiki version:

1.9

+--------------+-----------------+------+-----+---------+-------+
| Field        | Type            | Null | Key | Default | Extra |
+--------------+-----------------+------+-----+---------+-------+
| qc_type      | char(32)        | NO   | MUL | NULL    |       |
| qc_value     | int(5) unsigned | NO   |     | 0       |       |
| qc_namespace | int(11)         | NO   |     | 0       |       |
| qc_title     | char(255)       | NO   |     | NULL    |       |
+--------------+-----------------+------+-----+---------+-------+

MediaWiki version:

1.11

+--------------+------------------+------+-----+---------+-------+
| Field        | Type             | Null | Key | Default | Extra |
+--------------+------------------+------+-----+---------+-------+
| qc_type      | varbinary(32)    | NO   | MUL | NULL    |       |
| qc_value     | int(10) unsigned | NO   |     | 0       |       |
| qc_namespace | int(11)          | NO   |     | 0       |       |
| qc_title     | varchar(255)     | NO   |     | NULL    |       |
+--------------+------------------+------+-----+---------+-------+

MediaWiki version:

1.12

+--------------+-----------------+------+-----+---------+-------+
| Field        | Type            | Null | Key | Default | Extra |
+--------------+-----------------+------+-----+---------+-------+
| qc_type      | char(32)        | NO   | MUL | NULL    |       |
| qc_value     | int(5) unsigned | NO   |     | 0       |       |
| qc_namespace | int(11)         | NO   |     | 0       |       |
| qc_title     | char(255)       | NO   |     | NULL    |       |
+--------------+-----------------+------+-----+---------+-------+

DatabasesManual:Database layout

Engines: MySQLManual:MySQL – OracleManual:Oracle – PostgreSQLManual:PostgreSQL – SQLiteManual:SQLite Technical documentation: SchemaManual:Database layout (tablesCategory:MediaWiki database tables) – API property associationsAPI:Database field and API property associations – Field prefixesDatabase field prefixes – Primary key storage in other fieldsManual:Primary key storage in other fields – Wikimedia extension tablesCategory:Wikimedia extension database tables Configuration: SettingsManual:Configuration_settings#Database_settings – SharingManual:Shared database Development: AccessManual:Database access – OptimizationDatabase optimization – PolicyDevelopment policy#Database_patches – UpdaterManual:DatabaseUpdater.php – Extension schema updatesManual:Hooks/LoadExtensionSchemaUpdates – Patch fileManual:SQL patch file Core tables: archive – category – categorylinks – change_tag – config – externallinks – filearchive – hitcounter – image – imagelinks – interwiki – iwlinks – ipblocks – job – l10n_cache – langlinks – logging – log_search – msg_resource – msg_resource_links – module_deps – objectcache – oldimage – page – pagelinks – page_props – page_restrictions – protected_titles – querycache – querycachetwo – querycache_info – recentchanges – redirect – revision – searchindex – sites – site_stats – tag_summary – templatelinks – text – transcache – updatelog – uploadstash – user – user_former_groups – user_groups – user_newtalk – user_properties – valid_tag – watchlist