Linq to Entity Query with Subquery return error

Question

I've got a Linq to Entity query with a subquery that is returning an error that i'm hoping someone will be able to help me with.

Error Message:

"Unable to create a constant value of type 'SmallBusinessManager.Models.TransactionAllocation'. Only primitive types ('such as Int32, String, and Guid') are supported in this context."

Linq Query:

var query = from transactionSelect in smallBusinessManagerDB.Transaction
        select new
        {
         TransactionId = transactionSelect.TransactionId,
         TransactionNumber = transactionSelect.TransactionNumber,
         Amount = transactionSelect.Amount,
         Balance = (from t2 in smallBusinessManagerDB.TransactionAllocation
                    where t2.InvoiceTransactionId == transactionSelect.TransactionId
                    group t2 by t2.TransactionAllocationId into g
                    select g.Sum(p => p.AllocatedAmount))
};

Thanks in advance,

Chris

Answer 1

Try this:

var query = 
    from transactionSelect in smallBusinessManagerDB.Transaction
    select new
    {
        TransactionId = transactionSelect.TransactionId,
        TransactionNumber = transactionSelect.TransactionNumber,
        Amount = transactionSelect.Amount,
        Balance = smallBusinessManagerDB.TransactionAllocation
            .Where(t2 => t2.InvoiceTransactionId == transactionSelect.TransactionId)
            .Sum(p => p.AllocatedAmount)
    };