Manual:linktarget table

Manual:Contents MediaWiki database layout linktarget table
MediaWiki version:
1.38

This table stores a page namespace-title tuples, each one with a unique integer ID. This table is used for referenced page titles in tables that track links to pages: templatelinks, categorylinks, pagelinks and imagelinks tables.

This table contains immutable rows, which means only new rows are inserted, and never deleted or updated during normal wiki operation. However, the pruneUnusedLinkTargetRows.php maintenance script can be run to delete unused entries.

Access to this table from code is handled by instances of the class MediaWiki\Linker\LinkTargetLookup interface.

During schema migration, this table is filled using the migrateLinksTable.php maintenance script. $wgTemplateLinksSchemaMigrationStage controls whether data is read/written to this table.

Fields

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lt_id

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Primary key.

lt_namespace

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Namespace of the link target.

lt_title

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Text part of link target excluding namespace.

Schema summary

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MediaWiki version:
1.38

DESCRIBE linktarget;

+--------------+---------------------+------+-----+---------+----------------+
| Field        | Type                | Null | Key | Default | Extra          |
+--------------+---------------------+------+-----+---------+----------------+
| lt_id        | bigint(20) unsigned | NO   | PRI | NULL    | auto_increment |
| lt_namespace | int(11)             | NO   | MUL | NULL    |                |
| lt_title     | varbinary(255)      | NO   |     | NULL    |                |
+--------------+---------------------+------+-----+---------+----------------+

Indexes

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MediaWiki version:
1.38
Gerrit change 754989

SHOW INDEX IN linktarget;

+------------+------------+--------------------+--------------+--------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table      | Non_unique | Key_name           | Seq_in_index | Column_name  | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+------------+------------+--------------------+--------------+--------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| linktarget |          0 | PRIMARY            |            1 | lt_id        | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| linktarget |          0 | lt_namespace_title |            1 | lt_namespace | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| linktarget |          0 | lt_namespace_title |            2 | lt_title     | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
+------------+------------+--------------------+--------------+--------------+-----------+-------------+----------+--------+------+------------+---------+---------------+