I just noticed some reports on Tendril for the following query on Commons:
SELECT /* ApiQueryUserContribs::execute */ rev_id, rev_page, rev_timestamp, rev_minor_edit, rev_deleted, rev_len, rev_parent_id, rev_sha1, comment_rev_comment.comment_text AS `rev_comment_text`, comment_rev_comment.comment_data AS `rev_comment_data`, comment_rev_comment.comment_id AS `rev_comment_cid`, actor_rev_user.actor_user AS `rev_user`, actor_rev_user.actor_name AS `rev_user_text`, temp_rev_user.revactor_actor AS `rev_actor`, page_namespace, page_title, page_id, page_latest, page_is_redirect, page_len FROM `revision` JOIN `revision_comment_temp` `temp_rev_comment` ON ((temp_rev_comment.revcomment_rev = rev_id)) JOIN `comment` `comment_rev_comment` ON ((comment_rev_comment.comment_id = temp_rev_comment.revcomment_comment_id)) JOIN `revision_actor_temp` `temp_rev_user` ON ((temp_rev_user.revactor_rev = rev_id)) JOIN `actor` `actor_rev_user` ON ((actor_rev_user.actor_id = temp_rev_user.revactor_actor)) JOIN `page` ON ((page_id = rev_page)) WHERE ((temp_rev_user.revactor_actor IN ('1224180', '14796') )) AND ((rev_deleted & 4) != 4) AND (revactor_timestamp<='20190422155900') AND (revactor_timestamp>='20190315160000') AND page_namespace = '6' AND (rev_parent_id = 0) ORDER BY rev_actor DESC, revactor_timestamp DESC, revactor_rev DESC LIMIT 501;Which looks like it is doing a full scan:
root@db1081.eqiad.wmnet[(none)]> show explain for 1361484607; +------+-------------+---------------------+--------+--------------------------------------------------------+-----------------+---------+----------------------------------------------------+-----------+--------------------------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +------+-------------+---------------------+--------+--------------------------------------------------------+-----------------+---------+----------------------------------------------------+-----------+--------------------------------------------------------------+ | 1 | SIMPLE | actor_rev_user | range | PRIMARY | PRIMARY | 8 | NULL | 2 | Using where; Using temporary; Using filesort | | 1 | SIMPLE | temp_rev_user | index | PRIMARY,revactor_rev,actor_timestamp | actor_timestamp | 22 | NULL | 289808903 | Using where; Using index; Using join buffer (flat, BNL join) | | 1 | SIMPLE | temp_rev_comment | eq_ref | PRIMARY,revcomment_rev | revcomment_rev | 4 | commonswiki.temp_rev_user.revactor_rev | 1 | Using index | | 1 | SIMPLE | comment_rev_comment | eq_ref | PRIMARY | PRIMARY | 8 | commonswiki.temp_rev_comment.revcomment_comment_id | 1 | | | 1 | SIMPLE | revision | eq_ref | PRIMARY,page_timestamp,rev_page_id,page_user_timestamp | PRIMARY | 4 | commonswiki.temp_rev_user.revactor_rev | 1 | Using where | | 1 | SIMPLE | page | eq_ref | PRIMARY,name_title | PRIMARY | 4 | commonswiki.revision.rev_page | 1 | Using where | +------+-------------+---------------------+--------+--------------------------------------------------------+-----------------+---------+----------------------------------------------------+-----------+--------------------------------------------------------------+ 6 rows in set, 1 warning (0.00 sec)
Query time:
3 rows in set (1 min 28.46 sec)