When you do context.Entry(entity).State = EntityState.Modified;, you are not only attaching the entity to the DbContext, you are also marking the whole entity as dirty. This means that when you do context.SaveChanges(), EF will generate an update statement that will update all the fields of the entity. This is not always desired. On the other … Read more
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
This is a topic I’m very interested in. There are many purists who say that you shouldn’t test technologies such as EF and NHibernate. They are right, they’re already very stringently tested and as a previous answer stated it’s often pointless to spend vast amounts of time testing what you don’t own. However, you do … Read more
On EF6.2, you can use HasIndex() to add indexes for migration through fluent API. https://github.com/aspnet/EntityFramework6/issues/274 Example modelBuilder .Entity<User>() .HasIndex(u => u.Email) .IsUnique(); On EF6.1 onwards, you can use IndexAnnotation() to add indexes for migration in your fluent API. http://msdn.microsoft.com/en-us/data/jj591617.aspx#PropertyIndex You must add reference to: using System.Data.Entity.Infrastructure.Annotations; Basic Example Here is a simple usage, adding an … 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
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.