How to switch between many databases without having to manually execute lots of USE DB queries

Question

I have a PHP script that reads and writes from multiple databases. I am using the mysqli extension. I connect to servers like this:

$link = new mysqli( $host, $user, $passwd );

The problem is that in my code I have to keep doing this when I want to read/write from a different database:

$this->link->select_db( 'some_db' );

but it's a pain having to remember to select the DB before using it.

I could do this:

$link1 = new mysqli( $host, $user, $passwd, $db1 );
$link2 = new mysqli( $host, $user, $passwd, $db2 );
...
...

but why make many connections to a host when I should only need one? Even though there are multiple DBs.

Is there a way you're meant to do this?

Thank you :).

Answer 1

Use 2-part object names?

SELECT * FROM db1.SomeTable;
CALL db2.SomeProc();