Question

I am using linq to Entity to retrieve data from to different tables by joining them, but I also want to group them by the field problemDesc in order to get rid of unnecessary duplicate entries for the same problem.

here is the code:

using (AssistantEntities context = new AssistantEntities())
        {
            var problems = context.tblProblems;
            var customers = context.tblCustomers;

            var query =
            from problem in problems
            join customer in customers
            on problem.CustID equals customer.custID
            where problem.IsActive == true
            orderby customer.isMonthlyService == true descending
            select new
            {
                problemID = problem.problemID,
                ProblemCreateDate = problem.ProblemCreateDate,
                CustID = problem.CustID,
                name = customer.name,
                isMonthlyService = customer.isMonthlyService,
                StationName = problem.StationName,
                problemDesc = problem.problemDesc,
                LogMeIn = problem.LogMeIn
            };
            return query.ToList();
        }

I am doing query.toList() in order to use that list in a gridview as a dataSource.
and if it possible, also add a field that count the duplicate problems.

Answer 1

You have plenty of examples in the following link.

LINQ – Grouping Operators