set the Database.SetInitializer to null. public class DatabaseContext: DbContext { //the base accepts the name of the connection string provided in the web.config as a parameter public DatabaseContext() : base(“DatabaseContext”) { //disable initializer Database.SetInitializer<DatabaseContext>(null); }
Well 26.10.2017 Entity Framework 6.2 was officially released. It includes a possibility to define indexes with ease via Fluent API. Ho it is to use was already announced in the beta of 6.2. Now you can use the HasIndex() method, followed by IsUnique() if it should be an unique index. Just a small comparison (before/after) … Read more
I would test it first to be sure. Performance doesn’t have to be that bad. If you need to enter all rows in one transaction, call it after all of AddToClassName class. If rows can be entered independently, save changes after every row. Database consistence is important. Second option I don’t like. It would be … Read more
You will not find an equivalent method in EF 7. By convention, a property whose CLR type can contain null will be configured as optional. So what decide if the relationship is optional or not is if the FK property is nullable or not respectively. In summary, due to your Message_Id FK property is string, … Read more
Now that you have read everyone’s reply, I will give you the correct answer. EF does not support lazy loading of properties. However it does support a much powerful concept then this. It’s called table splitting where you can map a table to two entities. Say a product table in the the database can be … Read more
Can you do this with the Entity Framework? Yes; it’s easy. Can you do this with the Entity Framework designer? Unfortunately, that is much harder. The problem you’re having is that the column exists in the storage schema (SSDL) in your EDMX. Removing the column with the GUI designer simply removes it from the client … Read more
The DataType Attribute is a Validation Attribute. You need to do that using the ModelBuilder. public class MyContext : DbContext { public DbSet<MyClass> MyClass; protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity<MyClass>().Property(x => x.SnachCount).HasPrecision(16, 3); modelBuilder.Entity<MyClass>().Property(x => x.MinimumStock).HasPrecision(16, 3); modelBuilder.Entity<MyClass>().Property(x => x.MaximumStock).HasPrecision(16, 3); } }
You’ve removed the wrong convention (PluralizingEntitySetNameConvention) for this purpose. Just replace your OnModelCreating method with the below and you will be good to go. using System.Data.Entity.ModelConfiguration.Conventions.Edm.Db; … protected override void OnModelCreating(ModelBuilder modelBuilder) { modelBuilder.Conventions.Remove<PluralizingTableNameConvention>(); } With Entity Framework 6, on your file that inherit from DbContext: using System.Data.Entity.ModelConfiguration.Conventions; protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Conventions.Remove<PluralizingTableNameConvention>(); … Read more
The exception explains clearly that there is only one asynchronous operation per context allowed at a time. So, you either have to await them one at a time as the error message suggests: var banner = await context.Banners.ToListAsync(); var newsGroup = await context.NewsGroups.ToListAsync(); Or you can use multiple contexts: var banner = context1.Banners.ToListAsync(); var newsGroup … Read more
I ran into the same problem. I didn’t really solve it, but I managed to get a little nasty workaround running, so i can deploy my solution to AppHarbor 😉 Its a IDatabaseInitializer implementation, that doesn’t delete the db, but just nukes all the constraints and tables, and then uses the ObjectContext.CreateDatabaseScript() method to generate … Read more