Select query from two databases

[Pbear74]

I can't figure this out.
I have two tables in two different dbs, they are not alike at all but do have one column that is the same.

Table A contains all users in the company.
Table B contains users that have access to an application.

I want to get the list of users from Table A that do not exist in Table B.

Should I be using Union or Joins?
Examples please.


Thanks in advance.

[NogDog]

I'm thinking maybe a nested query?

SELECT * FROM database_1.table_a WHERE user NOT IN (
   SELECT user FROM database_2.table_b
)

[Pbear74]

thanks nogdog, that did it.