SQLite -Refer a database to another database

I have two SQLite databases in my android app.One stores data of signup members and second one stores the products added by members.Currently it shows all products selected by all members in that database.But I want to display products added only by the loggedin member at a time.How can I refer the logged in user and products he added only by him

1st database : shopping ; its table : contacts

2nd database : addcart ; its table : add2cart