In the interest of making and keeping Wiki Replicas a stable and performant service, a new backend architecture is needed. There is some impact in the features and usage patterns.
If you do SQL queries to the Wiki Replicas via Quarry, PAWS, or some other way, these changes may impact you:
- Cross database JOINs will no longer work
- Unfortunately, this means cross joins from, for instance, enwiki to commonswiki or wikidatawiki are no longer possible
- Can only query a database if you are connected to it explicitly
- For example, connecting to the enwiki host to query against avwiki will no longer work
If you think you could be affected by these changes, please post a comment and link to the code you have that does the SQL queries, and we can try and help diagnose if you would be affected and how to change it so that it doesn't break if possible when the new system goes live.