This is a great question. First of all, here are a couple of workarounds that come to mind (they all require changes to the query): First workaround This one maybe a bit obvious and unfortunately not generally applicable: If the selection of items you would need to pass over to Enumerable.Contains already exists in a … Read more
You can’t map two regular entities into same table. You have several choices: Use table splitting. Use custom query with projection to non entity type (as @Aducci proposed) Use QueryView Use database view or directly DefiningQuery Table splitting Table splitting allows you to map a table into two entities in 1:1 relation. First entity will … Read more
I perfectly understand where you’re coming from. This is one of the biggest annoyances I’ve had to deal with when trying to get to grips with the EF and, apparently, it’s a very common issue. The solution that worked for me was to open the EDMX with the view in designer mode and assign a … Read more
The problem was that we were NOT using the factory pattern that MS recommends. You can use Factory implementation to get an instance of UserManager from the OWIN context. … This is a recommended way of getting an instance of UserManager per request for the application. As a result, “the same context instance is accessed … Read more
You need to add a blank “merge” migration that will reset the snapshot of the latest migration in the .resx file. Do this using the IgnoreChanges switch: Add-Migration <migration name> -IgnoreChanges See here for an explanation
Entity Framework (version 6.1.3) and MySQL Server (>= 5.7.6) One way to resolve the issue is, 1. Open Services (services.msc) and restart MySQL57 service. 2. Execute the following commands in MySQL. use <<database name>>; set global optimizer_switch=”derived_merge=OFF”; 3. Update the .edmx. It’s a late reply. But hope it will help somebody. Thanks.
As mentioned by @anon you can’t attach model once you loaded the entity with the same key. The changes must be applied to attached entity. Instead of this: db.Entry(model).State = EntityState.Modified; use this: db.Entry(v).CurrentValues.SetValues(model);
Try this: var orderKeys = new int[] { 1, 12, 306, 284, 50047}; var orders = (from order in context.Orders where orderKeys.Contains(order.Key); select order).ToList(); Assert.AreEqual(orderKeys.Count, orders.Count); Edit: I have found some workarounds for this issue – please see WHERE IN clause?: The Entity Framework does not currently support collection-valued parameters (‘statusesToFind’ in your example). To … Read more
Using any context.XyzAsync() method is only useful if you either await the called method or return control to a calling thread that’s doesn’t have context in its scope. A DbContext instance isn’t thread-safe: you should never ever use it in parallel threads. Which means, just for sure, never use it in multiple threads anyway, even … Read more
Use ColumnAttribute to give the datatype [Column(TypeName = “VARCHAR”)] [StringLength(250)] public string Comment { get; set; } Or use fluent API modelBuilder.Entity<MyEntity>() .Property(e => e.Comment).HasColumnType(“VARCHAR”).HasMaxLength(250);