Relationship between two tables in SQL Server

Question

I have two tables in LibraryDB. One is Book_Master and the other is Languages. I have used langid in Book_Master as a Foreign Key and want to make a relationship between these two tables but I've got an error. Picture is given in the description. Help me Programmers..!! Here is the picture Click to see image

Answer 1

Analyze your tables.

select b.LangID
from book_master b
left join Languages L on b.LangID = L.LangID
where L.LangID is null

The result is LangID's in Book_master which don't exist in Languages (and block FK creation).