Hello, In the documentation of $wgDBprefix [0], it has been explicitly mentioned that you should not set this if you're using Postgres as your DBMS since 2006.

We are depending on this assumption on new places now [1] and if you set this, please unset and fix your database ASAP otherwise you end up with some tables that have the prefix and some that don't which I assume wouldn't be really fun.

Thank you for your understanding

[0]: https://www.mediawiki.org/wiki/Manual:$wgDBprefix [1]: https://gerrit.wikimedia.org/r/c/mediawiki/core/+/595316#message-9c1b408f7be...

Best