How to reference another table in In-DB workflow formula?

skyfire165

I have a table from SQL in-DB coming in and I want to create a new field with a formula. However in this formula, I am referencing another table and I do not know how to do that using in-DB alteryx tools. Here is an example of the SQL query I am trying to convert to Alteryx:

select 

case when (Select code from TableA a where a.id = b.id) = "AAA") = 'A'

         when (Select code from TableC c where c.id = b.id) = "CCC") = 'C'

from TableB b

This is a very simple example and might not make 100% sense, but the point is I'm not sure how to reference things from another table like TableA and TableC when writing a formula for a new field in TableB.

Thanks

JoeS

Sorry, what I meant is making sure that the table name isn't referred to on it's own in the formula. So to have the database, schema and table name. 

Like my example 

[Alteryx].[dbo].[Transactions_UK]

You don't need to do anything with other Connect In-DB tools, you can just refer to it in the formula tool. It's just the case statement that goes in there though, you don't need the select, as that's handle by Alteryx for you.