Question

I tries to delete an entity – table

This is the code:

db.Sessions.SqlQuery("delete table session");
db.SaveChanges();

This isnt delete the table. Or do anything..
db is inherits from DbContext object.

I’ve found a solution

foreach (var item in db.Sessions)
{
    db.Sessions.Remove(item);
}

db.SaveChanges();

But I’m sure theres a better way.

Thanks.

Answer 1

SqlQuery as the name implies only for executing queries if you want to drop the table you need something else:

With the use of the DbContext.Database property you can execute any DDL/DML query:

db.DataBase.ExecuteSqlCommand("drop table sessions");

I have also created a repro and it’s working fine with EF4.3.1 with SQL Server2008:

using (var db = new EFRepros())
{
    db.Sessions.Add(new Session() { Name = "Test1" });
    db.Sessions.Add(new Session() { Name = "Test2" });
    db.Sessions.Add(new Session() { Name = "Test3" });
    db.SaveChanges();
    Console.WriteLine(db.Sessions.Count()); // Output: 3
    db.Database.ExecuteSqlCommand("delete from sessions");
    //db.Database.ExecuteSqlCommand("truncate table sessions"); //this also works
    Console.WriteLine(db.Sessions.Count()); // Output: 0
}

Note: EF by default use plurar table names so you need to use sessions.