On at least enwiki, there is a "hashs" database table that appears to be unused and unneeded. It also is an apparent misspelling ("hashes" is the plural of "hash" in English).
Its schema:
MariaDB [enwiki_p]> describe hashs;
+--------------+-----------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-----------------+------+-----+---------+-------+
| hs_nstitle | varbinary(48) | YES | | NULL | |
| hs_timestamp | varbinary(14) | YES | | NULL | |
| hs_old_id | int(8) unsigned | YES | | NULL | |
| hs_hash | varbinary(48) | YES | | NULL | |
| hs_user_text | varbinary(255) | YES | | NULL | |
+--------------+-----------------+------+-----+---------+-------+
5 rows in set (0.02 sec)
This database table should be dropped from all Wikimedia wikis.
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**Version**: wmf-deployment
**Severity**: enhancement