i have 2 separate tables.one is coming from one source. Other is coming from different source.
i Want to join those 2 tables in logical layer and display in presentation layer under one catalog.
do I need to follow any steps to get this work? Direct joining would work in logical layer between those 2 tables.
You still have to join them in the physical layer first because the logical join must be translated into something and that "something" is defined by the physical join. You can perfectly define a physical join between objects of different sources.
(just keep in mind that if your sources are different it's the BI server doing the work and not your DB...)