如何通过实体框架在C＃中使用本机SQL查询

Question

I want to use this query

select datename (dw, CURRENT_TIMESTAMP)AS DAY ;

to get week day name and use it to insert record to table.

how can I use this query by entity framework

I use this method but it doesn't work:

   private void GetDayName(DateTime ReportDate,out string DayName)
    {
     using (var context = new Daily_ReportEntities3())
     {
       var day_name= context.ExecuteStoreQuery ("select datename (dw,'|| + ReportDate + ||') as NameOfDay", null).ToList();

    DayName = day_name=.ToString();
      }
    }

Answer 1

You cannot execute transact SQL statements from Entity Framework directly.

But you can Execute Functions from within ObjectContext .

First define a scalar value function returning data you need and next import it to your Store model. You'll be able to execute it via ObjectContext.ExecuteFunction method.

---

PS. Consider implementing your functionality using System.Globalization.Calendar object, that can supply the information about day names based on certain culture.

Answer 2

Should be like this:

var day_name = context.Database.SqlQuery<string>
     ("select datename (dw,'|| + ReportDate + ||') as NameOfDay").FirstOrDefault<string>();

see
http://msdn.microsoft.com/en-us/library/gg696545%28v=vs.103%29.aspx