It seems that some pages which have been deleted from English Wikipedia still exist in the page tables on some database replicas:
Production:
mysql:wikiadmin@db1089 [enwiki]> select * from page where page_namespace = 0 AND page_title LIKE 'BatissForever'; Empty set (0.00 sec)
Tool Labs:
MariaDB [enwiki_p]> select * from page where page_namespace = 0 AND page_title LIKE 'BatissForever'; +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+ | page_id | page_namespace | page_title | page_restrictions | page_counter | page_is_redirect | page_is_new | page_random | page_touched | page_links_updated | page_latest | page_len | page_content_model | +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+ | 49995280 | 0 | BatissForever | | 0 | 0 | 0 | 0.638177166992 | 20160331025325 | 20160330185410 | 712718594 | 212 | wikitext | +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+
Analytics Store:
mysql:research@analytics-store.eqiad.wmnet [enwiki]> select * from page where page_namespace = 0 AND page_title LIKE 'BatissForever'; +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+-----------+ | page_id | page_namespace | page_title | page_restrictions | page_counter | page_is_redirect | page_is_new | page_random | page_touched | page_links_updated | page_latest | page_len | page_content_model | page_lang | +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+-----------+ | 49995280 | 0 | BatissForever | | 0 | 0 | 0 | 0.638177166992 | 20160331025325 | 20160330185410 | 712718594 | 212 | wikitext | NULL | +----------+----------------+---------------+-------------------+--------------+------------------+-------------+----------------+----------------+--------------------+-------------+----------+--------------------+-----------+
But apparently s1-analytics slave matches Production and doesn't have this discrepancy:
mysql:research@s1-analytics-slave.eqiad.wmnet [enwiki]> select * from page where page_namespace = 0 AND page_title LIKE 'BatissForever'; Empty set (0.02 sec)
Some other pages that also appear on Tool Labs, but not in Production: Cyclone_Victor(1986), Mercurialsoft_inc