On Wed, Jan 17, 2018 at 5:50 PM, YiFei <zhuyifei1999@gmail.com> wrote:
SELECT ... FROM `<database>`.`<table>`, like in https://quarry.wmflabs.org/query/24212. This should work in the foreseeable future, during which all the replica databases are accessible on the same server.

This is bad advice. Just last week[1] one of our DBAs warned this list that that ability is not guaranteed or supported, and changing that is indeed a possibility.

[1]: https://lists.wikimedia.org/pipermail/cloud/2018-January/000169.html

Brad Jorsch (Anomie)
Senior Software Engineer
Wikimedia Foundation