Connect a database with externals tables

I never made something similar .

I have a system and i need to relate my data with external data (in another database). My preference is get these data and create my own tables, but in this case when the other dbs are updated my personal tables will be obsolete.

So, basically i need to synchronize my tables with external tables, or just get the external data values.

I don’t have any idea how i can connect and relate data from ten external databases.

I need to check if an user is registered in another websites, basically.

Any help?

Another database on the same server, or on another server entirely? Cause those are different things.

in another server. thanks

Well from another server you’re going to have issues.

Do you have full access to the external database server? (IE: To set up some sort of replication)

If not, you’re going to have to use an intermediate system (PHP or such) to retrieve the data from each server individually, and then compile it.