Hi Frans

I have the following query against the Northwind database:

LinqMetaData meta = new LinqMetaData(adapter);

var query = from e in meta.Employee
        join o in meta.Order on e.Id equals o.EmployeeId
        join c in meta.Customer on o.CustomerId equals c.CustomerId
        where c.CustomerId == "ALFKI"
        select e;

query = query.OrderBy(e => e.City).ThenBy(e => e.Region);

Note that I renamed the EmployeeId field to just Id

This causes the following exception: "Invalid column name 'EmployeeID'."

Because the following invalid SQL was generated:

exec sp_executesql N'
SELECT 
    [LPA_L1].[EmployeeID] AS [Id], 
    [LPA_L1].[LastName], [LPA_L1].[FirstName], 
    [LPA_L1].[Title], [LPA_L1].[TitleOfCourtesy], 
    [LPA_L1].[BirthDate], 
    [LPA_L1].[HireDate], 
    [LPA_L1].[Address], 
    [LPA_L1].[City], 
    [LPA_L1].[Region], 
    [LPA_L1].[PostalCode], 
    [LPA_L1].[Country], 
    [LPA_L1].[HomePhone], 
    [LPA_L1].[Extension], 
    [LPA_L1].[Photo], 
    [LPA_L1].[Notes], 
    [LPA_L1].[ReportsTo], 
    [LPA_L1].[PhotoPath] 
FROM (
    SELECT 
        [LPA_L2].[EmployeeID] AS [Id], 
        [LPA_L2].[LastName], 
        [LPA_L2].[FirstName], 
        [LPA_L2].[Title], 
        [LPA_L2].[TitleOfCourtesy], 
        [LPA_L2].[BirthDate], 
        [LPA_L2].[HireDate], 
        [LPA_L2].[Address], 
        [LPA_L2].[City], 
        [LPA_L2].[Region], 
        [LPA_L2].[PostalCode], 
        [LPA_L2].[Country], 
        [LPA_L2].[HomePhone], 
        [LPA_L2].[Extension], 
        [LPA_L2].[Photo], 
        [LPA_L2].[Notes], 
        [LPA_L2].[ReportsTo], 
        [LPA_L2].[PhotoPath] 
    FROM (( 
        [Northwind].[dbo].[Employees] [LPA_L2]  
        INNER JOIN [Northwind].[dbo].[Orders] [LPA_L3]  
            ON  [LPA_L2].[EmployeeID] = [LPA_L3].[EmployeeID]) 
        INNER JOIN [Northwind].[dbo].[Customers] [LPA_L4]  
            ON  [LPA_L3].[CustomerID] = [LPA_L4].[CustomerID]) 
        WHERE ( ( ( [LPA_L4].[CustomerID] = @CustomerId1)))) LPA_L1 
    ORDER BY 
        [LPA_L1].[City] ASC,
        [LPA_L1].[Region] ASC

',N'@CustomerId1 nchar(5)',@CustomerId1=N'ALFKI'

The outer query is trying to select EmployeeID as ID, but the inner query has already aliased it to ID.

If I remove the order by clause, the query works correctly as no subquery is created.

This is with today's build? (or with the original build) ? Never mind, the alias bug fixed in todays build isn't about this situation.

Indeed, something which should work. Will look into it.

Reproduced.

Heh I was looking at where to fix it, so I first added some code to the linq provider, then that failed and it wasn't a good idea, so I looked for a way to add a routine to runtime lib, where I found a routine which was already added for correcting the situation of your query (sometimes frameworks just get too big to get an overview of all the methods available ), but it had a small bug, after correcting that your query worked.

So fixed in next build.

Brilliant, thanks