ef-core-2.0

问题 I want to create a unit test to ensure no developer will commit model changes without the corresponding migration. How do I test that the database matches the DbContext? 回答1: You can leverage some of the lower-level Migrations components to do that: var migrationsAssembly = db.GetService<IMigrationsAssembly>(); var differ = db.GetService<IMigrationsModelDiffer>(); var hasDifferences = differ.HasDifferences( migrationsAssembly.ModelSnapshot.Model, db.Model); Assert.False(hasDifferences, "You

问题 I want to create a unit test to ensure no developer will commit model changes without the corresponding migration. How do I test that the database matches the DbContext? 回答1: You can leverage some of the lower-level Migrations components to do that: var migrationsAssembly = db.GetService<IMigrationsAssembly>(); var differ = db.GetService<IMigrationsModelDiffer>(); var hasDifferences = differ.HasDifferences( migrationsAssembly.ModelSnapshot.Model, db.Model); Assert.False(hasDifferences, "You

问题 In EF Core 2.0, we have the ability to derive from IEntityTypeConfiguration for cleaner Fluent API mappings (source). How can I extend this pattern to utilize a base entity? In the example below, how can I have a BaseEntityConfiguration to reduce duplication in LanguageConfiguration and MaintainerConfiguration , modifying properties that are in the BaseEntity only in the BaseEntityConfiguration ? What would such a BaseEntityConfiguration look like; and how would it be used, if at all, in

问题 In EF Core 2.0, we have the ability to derive from IEntityTypeConfiguration for cleaner Fluent API mappings (source). How can I extend this pattern to utilize a base entity? In the example below, how can I have a BaseEntityConfiguration to reduce duplication in LanguageConfiguration and MaintainerConfiguration , modifying properties that are in the BaseEntity only in the BaseEntityConfiguration ? What would such a BaseEntityConfiguration look like; and how would it be used, if at all, in

问题 I'm using ASP.Net Core 2.0 with Entity Framework and I am trying to return a model to a page that contains the Employment entity with it's collection of EmploymentDocument entities also included. For the latter I do not want to load the data (byte[]) column but I do want all the other columns, most importantly FileName. The linq query I have which loads everything including the data column is: var employment = await _context.Employment .Include(e => e.EmploymentDocuments) // will load all

问题 After having some experience with EF6 (like this), I wanted to try out EF Core, because I've read some articles and watched some videos saying that it outperforms EF6 by a very large margin. So, I made sample program with class: public interface IEntity { int Id { get; set; } } public class Employee : IEntity { public int Id { get; set; } public string FirstName { get; set; } public string Surname { get; set; } } Then I created a repository pattern with generic repository: public interface

问题 My table has four columns and I want to split it between multiple classes. table1 key col1 col2 col3 col4 Class ClassA key col1 col2 class ClassB key col3 col4 modelBuilder.Entity().ToTable("table1"); modelBuilder.Entity().ToTable("table1"); Currently it give me System.InvalidOperationException: 'Cannot use table 'table1' for entity type 'ClassB' since it is being used for entity type 'ClassA' Is it possible in EF Core? Thanks 回答1: You may need a relationship defined like the following based

问题 I am working on creating an ecommerce website on ASP MVC Core 2. I inherited my user from IdentityUser and inherited context from IdentityDbContext for working with user data and inherited a different context from DbContext for working with products and orders etc. Now, I want to link an order or shopping cart to a particular user and can not wrap my head around how to refer to the user in order table as they are in different contexts. I am also using the default guid created by EF as primary

问题 I have an M to N relationship on my Database. I took the sample Database "sakila" from the MySql page. I have set up my Model Objects as follows. Film Table public partial class Film { public Film() { FilmActor = new HashSet<FilmActor>(); FilmCategory = new HashSet<FilmCategory>(); Inventory = new HashSet<Inventory>(); } //Some Properties public ICollection<Inventory> Inventory { get; set; } } Linking Table Inventory public partial class Inventory { public Inventory() { Rental = new HashSet

问题 Following .net core EF core, Linq cannot be translated and will be evaluated locally. Can you please give me an advise? var temp1= (from so in context.OrderShippingOrders group so by so.OrderId into g where g.Count(x=> x.IsSent == true ) == g.Count() select new { g.Key } ); query = (from o in context.Orders join s in temp1 on o.Id equals s.Key select o ); The LINQ expression 'join AnonymousObject _o in {from Order o in value(Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable 1