LINQ Union between two tables with the same fields and then returned in a collection

Question

I have given up trying to create a linq query to retrieve a sql server view which is a union between two tables. I will now try to create a linq union.

I have two views, MemberDuesPaid and MemberDuesOwed. They have the same fields in both; (BatchNo, TranDate, DebitAmount, CreditAmount, ReceiptNo, CheckNo, SocSecNo).

I also have a helper class in my application which is called MemberTransaction. It has all the same properties.

How how do i do a union between the two tables where socSecNo = the ssn passed in? I want to union the two tables and return an IEnumerable collection of MemberTransaction. After the two tables are unioned together i want to have the collection that is returned ordered by trandate in descending order.

Answer 1

You can do it in a Linq Union query:

var infoQuery =
    (from paid in db.MemberDuesPaid 
    select new MemberTransaction() {
        BatchNo = paid.BatchNo,
        TranDate = paid.TranDate,
        DebitAmount = paid.DebitAmount,
        CreditAmount = paid.CreditAmount,
        ReceiptNo = paid.ReceiptNo,
        CheckNo = paid.CheckNo,
        SocSecNo = paid.SocSecNo})
    .Union
        (from owed in db.MemberDuesOwed
        select new MemberTransaction() {
        BatchNo = owed.BatchNo,
        TranDate = owed.TranDate,
        DebitAmount = owed.DebitAmount,
        CreditAmount = owed.CreditAmount,
        ReceiptNo = owed.ReceiptNo,
        CheckNo = owed.CheckNo,
        SocSecNo = owed.SocSecNo});

That should return you a set with everything combined into a single list.

[Edit]

If you want distinct values, you can do something like this after the above statement (you can do it inline if you bracket everything, but this is simpler to explain):

infoQuery = infoQuery.Distinct();

The variable infoQuery will by this time be populated entirely with objects of type MemberTransaction rather than the two disparate types in the union statement.