Best practice for sharing data over differenet mysql/mariadb databases I have app that uses DB with 50+ tables. Now i'm in situation that i need to install another instance of app. Problem is that i would like to use some tables as "common" data, e.g. "brands" or "cities" or "countries" in both (for now there are only 2, but it might soon be more) apps.

I searched and find that i can make "common" DB with such tables, and have views in each DB instance that points to corresponding table.

Main app queries are heavily relying on that common tables, so i'm concerned if that will slow down my queries since views don't have indexes?

Are there some better practices? I'm looking now for replication in mysql manual. Is that way to go? Replicate tables from common DB to app instance DB's? Can this be one-direction replication? (only tables in "common" DB can be changed and then replicated to other DB's)?

thanx for advice Y
If the "common" tables on the secondary "app instances" are being accessed read only, then your easiest option will be doing a traditional master slave(s) configuration with a replicate_ignore_table = ... line put into all slaves for all tables except the "common" ones.

If you need to have identical behavior between all app instances (meaning you're not using app logic to isolate writes to the master only), then I would seriously considering using a galera cluster product of some sort.