In LINQ Query convert the string to datetime and check with today's date

Question

In Table, DueDate data type is varchar. Now I want to check the due date with today\'s date

 var query = (from o in db.Order_Reports
              where Convert.         


        

Answer 1

The problem is that Linq-to-Entities is not capable of turning Convert.ToDateTime into valid sql. If you bring all the records into memory with a call to AsEnumerable() or ToList() then you will be using Linq-To-Sql and that will work with C# functions:

var query = (from o in db.Order_Reports.AsEnumerable()
              where DateTime.ParseExact(o.ReportDueDateTime, 
                                        "MM/dd/yyyy", 
                                        "M/d/yyyy") >= DateTime.Now
              select o);

The problem with that is that you might be bringing too many records into memory. But if you have enough reports for that to be a worry, then you should probably be putting a database index on that ReportDueDateTime and you need that index to be in date order. So change that column to a DateTime or change the data into a format that can be sorted alphabetically - like "YYYY-MM-DD-HH-mm". Then you could do this:

var query = (from o in db.Order_Reports
             where String.Compare(ReportDueDateTime, 
                                  DateTime.Now.ToString("YYYY-MM-DD-HH-mm")) >= 0
              select o);