Hello all,

This is an important announcement for all the tool builders and maintainers who access Wikidata’s data by querying directly Labs database replicas.

In May-June 2019, the Wikidata development team will drop the wb_terms table from the database in favor of a new optimized schema. Over years, this table has become too big, causing various issues.

This change requires the tools using wb_terms to be updated. Developers and maintainers will need to adapt their code to the new schema before the migration starts and switch to the new code when the migration starts.

The migration will start on May 29th. On May 15th, a test system will be available for you to test your code.

The table being used by plenty of external tools, we are setting up a process to make sure that the change can be done together with the developers and maintainers, without causing issues and broken tools. Most of the documentation and updates will take place on Phabricator:

We are aware that this change will ask you to make some important changes in your code, and we are willing to help you as much as our resources allow us to. We hope that you will understand that this change is made to avoid bigger issues in the near future.

Note that this change is not impacting Wikibase instances outside of Wikidata. A dedicated migration plan and announcement will follow.

We strongly encourage you to not wait until last minute to make the changes in your code. If you have any question or issue, we will be happy to help. In order to keep the discussions in one place, please ask questions or raise issues directly in the Phabricator task and board.

Thanks for your understanding,

Léa Lacroix
Project Manager Community Communication for Wikidata

Wikimedia Deutschland e.V.
Tempelhofer Ufer 23-24
10963 Berlin

Wikimedia Deutschland - Gesellschaft zur Förderung Freien Wissens e. V.

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