Hi everyone,
This is an important message to all the people running external tools.
About 2 years ago we said we want to get rid of the "wb_entity_per_page" table. This is still the case and is becoming more pressing now with the introduction of support for lexicographical data.
On July 12th, we are going to stop updating the "wb_entity_per_page" table from the Wikibase database and stop its replication on ToolLabs. At a later point we will remove it completely.
"wb_entity_per_page" was a secondary database table, mapping Wikibase entity IDs (e.g. "Q42") to MediaWiki page IDs (e.g. 138, which can be seen at https://www.wikidata.org/wiki/Q42?action=info). "wb_entity_per_page" stored entity IDs as numbers, while page titles are always full entity IDs.
This mapping existed because Wikibase was designed with the possibility to have entity pages where the ID does not match the title. This idea was never used, and finally removed in 2015 (documented in https://phabricator.wikimedia.org/T95685). We decided to get rid of the table because it contains outdated information that could mislead users, it costs resources and could conflict in the future with our new entity types for lexicographical data.
Please check if you are maintaining any code that accesses the "wb_entity_per_page" table, and replace it with lookups to MediaWiki's "page" and "redirect" tables.
We will drop the replica of the table on ToolLabs for test.wikidata.org on June 28th. We will do the same for wikidata.org on July 12th.
If you have any question or issue, feel free to add a comment on the ticket (http://phabricator.wikimedia.org/T95685) or to ping me. Thanks for your understanding
Cheers Lydia