News/2025 Wikidata term store database split

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This page contains information about the split of Wikidata term store tables to the new x3 database cluster.

What is changing?

Tables holding Wikidata's term store (wbt_*) are being split to a new separate database cluster. Tools querying those tables via the wiki replicas must be adapted to connect to the new cluster instead.

Timeline

• Done 2025-04-24: New hostnames announced and ready for use.
• TBD: Cluster is split. The tables on the old s8 cluster will no longer be updated and will eventually be dropped.

What should I do?

If you maintain a tool that queries the Wikidata term store tables (wbt_*), you need to update your code to connect to a separate database cluster for those:

Old hostname	New hostname
wikidatawiki.analytics.db.svc.wikimedia.cloud	termstore.wikidatawiki.analytics.db.svc.wikimedia.cloud
wikidatawiki.web.db.svc.wikimedia.cloud	termstore.wikidatawiki.web.db.svc.wikimedia.cloud

In addition, any code performing JOINs between those tables and other wikidatawiki will need to be changed to perform the same operations in code instead.

Alternatively, you may be able to change your code to read terms from a different, more stable source, such as the wbgetentities API (potentially with the languages= and languagefallback= parameters) or the wbformatentities API. These APIs will keep working even if further changes to the term store in the database are necessary in future.

Why are we doing this?

Wikidata's database has been growing too fast, and so this change is necessary to allow growth and to improve Wikidata's performance.

See also

• Help:Wiki Replicas
• [Wikitech-l] Re: Several database changes happening in the coming months

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