Question

I’m really, really struggling with what should otherwise be a straightforward query in anything other than LINQ (for example SQL!)

I have two entities:

Product
ProductApprover

The Product entity has a one to many relationship on the ProductApprover entity, e.g:

Product.ProductApprovers gives me all ProductApprover entities relating to the Product.

Getting a Product and associated ProductApprover data is simple enough when querying by my ProductID column on my Product entity as the ProductApprover data associated is bundled into the result automatically, but my problem comes when I want to alter my query by querying data WITHIN my associated ProductApprover entities. I have tried all sorts with use of the ‘Where’, ‘Contains’ and ‘Any’, functions, etc, to perform a subquery, but cannot seem to get the result I want.

The query I want to perform is:

SELECT * FROM Product p
INNER JOIN ProductApprover pa ON p.ProductId = pa.ProductId
WHERE p.ProductId = @id AND pa.Version = @version

Can anybody help me out please? Thank you kindly in advance.

Answer 1

Try this (I guess this is a LINQ interpretation of your SQL query):

int id = 123;
int version = 555;

var results = from p in context.Products 
              join pa in context.ProductApprovers 
              on p.ProductId = pa.ProductId 
              where p.ProductId equals id && pa.Version equals version
              select new { Product = p, Approver = pa };