Manual:Change tag def table

MediaWiki database layout

change_tag_def table

MediaWiki version:

≥ 1.32

The change_tag_def table is a table defining tag names for IDs. It also stores hit counts to avoid expensive queries on change_tag.

Fields

ctd_id

Numerical ID of the tag (change_tag.ct_tag_id refers to this)

ctd_name

Symbolic name of the tag (what would previously be put in change_tag.ct_tag)

ctd_user_defined

Whether this tag was defined manually by a privileged user using Special:Tags

ctd_count

Number of times this tag was used

Schema summary

MediaWiki version:

≥ 1.32

DESCRIBE change_tag_def;

+------------------+---------------------+------+-----+---------+----------------+
| Field            | Type                | Null | Key | Default | Extra          |
+------------------+---------------------+------+-----+---------+----------------+
| ctd_id           | int(10) unsigned    | NO   | PRI | NULL    | auto_increment |
| ctd_name         | varbinary(255)      | NO   | UNI | NULL    |                |
| ctd_user_defined | tinyint(1)          | NO   | MUL | NULL    |                |
| ctd_count        | bigint(20) unsigned | NO   | MUL | 0       |                |
+------------------+---------------------+------+-----+---------+----------------+

Indexes

MediaWiki version:

≥ 1.32

SHOW INDEX IN change_tag_def;

+----------------+------------+------------------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table          | Non_unique | Key_name         | Seq_in_index | Column_name      | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+----------------+------------+------------------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| change_tag_def |          0 | PRIMARY          |            1 | ctd_id           | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| change_tag_def |          0 | ctd_name         |            1 | ctd_name         | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| change_tag_def |          1 | ctd_count        |            1 | ctd_count        | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
| change_tag_def |          1 | ctd_user_defined |            1 | ctd_user_defined | A         |           0 |     NULL | NULL   |      | BTREE      |         |               |
+----------------+------------+------------------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+