Now, this works fine, but as you can see I’m calling .Include(u = u.Posts) twice. Is there a way to call ThenInclude twice on same property, without actually writing the Include statement also twice? Calling Include(u => u.Posts) twice is the right way to do it. From EF Core docs… emphasis on the last sentence. … Read more
All EF commands have this check: if (targetAssembly != migrationsAssembly) throw MigrationsAssemblyMismatchError; targetAssembly = the target project you are operating on. On the command line, it is the project in the current working directory. In Package Manager Console, it is whatever project is selected in the drop down box on the top right of that … Read more
Update for .NET 6 and later: EF logging is enabled by default in development. Just add “Microsoft.EntityFrameworkCore.Database.Command”: “Information” to appsettings.Development.json so it’s only logged in dev mode. You typically don’t want to log every query in a production app. { “ConnectionStrings”: { “DefaultConnection”: “Server=(localdb)\\mssqllocaldb;Database=MyDB-2;Trusted_Connection=True;MultipleActiveResultSets=true” }, “Logging”: { “LogLevel”: { “Default”: “Information”, “Microsoft”: “Warning”, “Microsoft.Hosting.Lifetime”: “Information” … Read more
The following call will clear the in-memory datastore. _context.Database.EnsureDeleted();
You can add a class that implements IDesignTimeDbContextFactory inside of your Web project. Here is the sample code: public class DesignTimeDbContextFactory : IDesignTimeDbContextFactory<CodingBlastDbContext> { public CodingBlastDbContext CreateDbContext(string[] args) { IConfigurationRoot configuration = new ConfigurationBuilder() .SetBasePath(Directory.GetCurrentDirectory()) .AddJsonFile(“appsettings.json”) .Build(); var builder = new DbContextOptionsBuilder<CodingBlastDbContext>(); var connectionString = configuration.GetConnectionString(“DefaultConnection”); builder.UseSqlServer(connectionString); return new CodingBlastDbContext(builder.Options); } } Then, navigate to … Read more
Two most important tips: [1] – Make sure that your project builds completely before you run a new scaffold command. Otherwise… You’ll start writing a line of code. You’ll realize a required DB column is missing from your model. You’ll go to try to scaffold it. Twenty minutes later you’ll realize the reason your build … Read more
Going to answer this one differently. Ideally the domain model should have no idea how data is stored. Adding backing fields and extra [NotMapped] properties is actually coupling your domain model to your infrastructure. Remember – your domain is king, and not the database. The database is just being used to store parts of your … Read more
Entity Framework core 5 is the first EF version to support filtered Include. How it works Supported operations: Where OrderBy(Descending)/ThenBy(Descending) Skip Take Some usage examples (from the original feature request and the github commmit) : Only one filter allowed per navigation, so for cases where the same navigation needs to be included multiple times (e.g. … Read more
I think this is an important question and should be well answered! What is Database.EnsureCreated? context.Database.EnsureCreated() is new EF core method which ensures that the database for the context exists. If it exists, no action is taken. If it does not exist then the database and all its schema are created and also it ensures … Read more
To update an entity with Entity Framework Core, this is the logical process: Create instance for DbContext class Retrieve entity by key Make changes on entity’s properties Save changes Update() method in DbContext: Begins tracking the given entity in the Modified state such that it will be updated in the database when SaveChanges() is called. … Read more