You definitely need to put in the column order, otherwise how is SQL Server supposed to know which one goes first? Here’s what you would need to do in your code: public class MyTable { [Key, Column(Order = 0)] public string SomeId { get; set; } [Key, Column(Order = 1)] public int OtherId { get; … Read more
In addition to adding these attributes to your Id column: [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public Guid Id { get; set; } in your migration you should change your CreateTable to add the defaultValueSQL property to your column i.e.: Id = c.Guid(nullable: false, identity: true, defaultValueSql: “newsequentialid()”), This will prevent you from having to manually touch your database … Read more
Your model is not a 1:1 association. You can still have many Class2 objects referring to the same one Class1 object. Also, your model doesn’t guarantee that a Class2 referring to a Class1 is also referred back by this Class1 object — Class1 can refer to any Class2 object. How to configure 1:1? The common … Read more
There are two ways to filter include Entity. Using a projection (See @Eldho answer) Using a third party library Disclaimer: I’m the owner of the project Entity Framework Plus The EF+ Query IncludeFilter allows to easily filter included entities. context.Entry(hotel) .Collection(x => x.Rooms) .Query() .IncludeFilter(y => y.Reservations .Where(z => z is ExecutiveSuite && z.Reservations.Any()) .Load(); … Read more
In Visual Studio 2012 all I had to do was enter: (localdb)\v11.0 Visual Studio 2015 and Visual Studio 2017 changed to: (localdb)\MSSQLLocalDB as the server name when adding a Microsoft SQL Server Data source in: View/Server Explorer/(Right click) Data Connections/Add Connection and then the database names were populated. I didn’t need to do all the … Read more
I’ve solved this problem with a little different approach a view month ago. Maybe it’s a good solution for you too. I didn’t want my solution to change the query itself. So a ids.ChunkContains(p.Id) or a special WhereContains method was unfeasible. Also should the solution be able to combine a Contains with another filter as … Read more
You’re trying to update the record (which to me means “change a value on an existing record and save it back”). So you need to retrieve the object, make a change, and save it. using (var db = new MyContextDB()) { var result = db.Books.SingleOrDefault(b => b.BookNumber == bookNumber); if (result != null) { result.SomeValue … Read more
Same problem, but i installed EF 6 through Nuget. EntityFramework.SqlServer was missing for another executable. I simply added the nuget package to that project.
This is an example of an extension method I wrote to populate the common values of two objects. public static void PopulateInto( this object source, object target, BindingFlags flags) { foreach (var pi in source.GetType().GetProperties(flags)) { var tpi = target.GetProperty(pi.Name, flags); if (tpi.IsNotNull()) { try { object originalValue; object value = originalValue = source.GetValue<object>(pi.Name, new … Read more