I would use a single Context class inheriting from IdentityDbContext. This way you can have the context be aware of any relations between your classes and the IdentityUser and Roles of the IdentityDbContext. There is very little overhead in the IdentityDbContext, it is basically a regular DbContext with two DbSets. One for the users and … Read more
int maxShoeSize = Workers.Where(x => x.CompanyId == 8) .Select(x => x.ShoeSize) .DefaultIfEmpty(0) .Max(); The zero in DefaultIfEmpty is not necessary.
You have 2 options: You can take the Down from the bad migration and put it in a new migration (you will also need to make the subsequent changes to the model). This is effectively rolling up to a better version. I use this option on things that have gone to multiple environments. The other … Read more
It’s not necessary to query the object first, you can attach it to the context by its id. Like this: var employer = new Employ { Id = 1 }; ctx.Employ.Attach(employer); ctx.Employ.Remove(employer); ctx.SaveChanges(); Alternatively, you can set the attached entry’s state to deleted : var employer = new Employ { Id = 1 }; ctx.Entry(employer).State … Read more
The easiest solution is to override SaveChanges on your entities class. You can catch the DbEntityValidationException, unwrap the actual errors and create a new DbEntityValidationException with the improved message. Create a partial class next to your SomethingSomething.Context.cs file. Use the code at the bottom of this post. That’s it. Your implementation will automatically use the … Read more
Is objects a Linq-To-SQL database context? In which case, you can only use simple expressions to the right of the => operator. The reason is, these expressions are not executed, but are converted to SQL to be executed against the database. Try this Arr[] myArray = objects.Select(o => new Obj() { Var1 = o.someVar, Var2 … Read more
Try this: var sql = @”Update [User] SET FirstName = @FirstName WHERE Id = @Id”; ctx.Database.ExecuteSqlCommand( sql, new SqlParameter(“@FirstName”, firstname), new SqlParameter(“@Id”, id));
I had this error and found a few solutions: Looking at your connection string, it looks valid. I found this blog post, the problem here is that they were using Integrated Security. If you are running on IIS, your IIS user needs access to the database. If you are using Entity Framework with Transactions, Entity … Read more
You can do it by manually edit code first migration: public override void Up() { AddColumn(“dbo.Events”, “Active”, c => c.Boolean(nullable: false, defaultValue: true)); }
You can have multiple contexts for single database. It can be useful for example if your database contains multiple database schemas and you want to handle each of them as separate self contained area. The problem is when you want to use code first to create your database – only single context in your application … Read more