Fabric - Row Level Security on Warehouse - Stage 2...

Okay, I managed to find a solution...

In my setup, I do have one table, that shows all users and which products each of them is allowed to see, e.g.:
Table ProductsPerUser

To derive the Products the user is allowed to see, I had to extend the security function as follows:

CREATE FUNCTION
    [SC_Security].[fn_securityProducts](@Product AS INT)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
    SELECT 1 AS result
    FROM
        ProductsPerUser PPU
        INNER JOIN
        Products PROD
        ON PPU.Product = PROD.Product
    WHERE (PPU.User = USER_NAME() OR USER_NAME() = 'dbo')
    AND PROD.Product = @Product
GO

Now, I can implement the security policy on each table that has the "Product" as a field.

Works like a charm...