Manual:Module deps table

module_deps table is for caching which local files a skin/module depends on that aren't registered directly.

Currently used for tracking images and LESS files that  depends on.

md_module
Module name

md_skin
Skin name

md_deps
JSON blob with file dependencies.

Since MediaWiki 1.25 (T37472),  now deletes the contents of the module_deps table, thus clearing the cache.

For versions of MediaWiki which do not yet have this fix in update.php, the workaround is to manually delete the contents of the module_deps table.

Schema summary
DESCRIBE module_deps; +---++--+-+-+---+ +---++--+-+-+---+ +---++--+-+-+---+
 * Field    | Type           | Null | Key | Default | Extra |
 * md_module | varbinary(255) | NO  | PRI | NULL    |       |
 * md_skin  | varbinary(32)  | NO   | PRI | NULL    |       |
 * md_deps  | mediumblob     | NO   |     | NULL    |       |