This is one of the top slow queries in tenderil:
155 324 50 7,873 db2059 wikiuser wikidatawiki SELECT /* ApiQueryPagePropNames::execute */ DISTINCT pp_propname FROM page_props ORDER BY pp_propname LIMIT 501 /* eca54e37324ba61f23cd87946fe72863 db2059 wikidatawiki 29s */
Query plan:
mysql:wikiadmin@db2052 [wikidatawiki]> EXPLAIN SELECT /* ApiQueryPagePropNames::execute */ DISTINCT pp_propname FROM `page_props` ORDER BY pp_propname LIMIT 501; +------+-------------+------------+-------+---------------+------------------+---------+------+----------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +------+-------------+------------+-------+---------------+------------------+---------+------+----------+-------------+ | 1 | SIMPLE | page_props | index | NULL | pp_propname_page | 66 | NULL | 59183780 | Using index | +------+-------------+------------+-------+---------------+------------------+---------+------+----------+-------------+ 1 row in set (0.00 sec)