Working with multiple Databases in SQLite WIndows Phone 8.1

I worked with Database apps in Windows Phone 8.1 SDSK for the first time. I made a basic CRUD app with single DB following this tutorial.

Now I wanted to move on to using multiple databases in a single app, like one is student details, other has student marks as foreign key. I could make two tables and use Primary key from one to the other but what is proper way to use foreign keys and doing other complex queries like joins etc? I haven't found any good documentations regarding this even on github pages of SQLite-NET.

I considered using SQLitePCL wrapper as well but again cannot find any documentation regarding multiplae DBs and complex queries, foreign key constraints etc.

How to proceed in this case? Any links or hints to proceed would be very helpful.

[ Also, there should be a SQLitePCL tag too, moderators/senior members if you think it is worthy? ]