entity-framework

问题 I am using Entity Framework 6.0 with Microsoft SQL Server. By default, the primary key it generates for a table is named like PK_dbo.TableName , where TableName is in a plural form, even though the actual name of the table is in a singular form. For example, I have a table named dbo.Employee . Yet the primary key denoted by EF 6 is PK_dbo.Employees . Is there any way to change the primary key to something like PK_TableName where the TableName is in a singular form? Update: Thanks for the

问题 I have a stored procedure that returns data from a multi-table query. To do this do I need to create a DbSet for each of the tables that are involved in the query? All the examples I find that use FromSql have a DbSet (e.g., Books in the below example) specified before the FromSql clause. using (var context = new SampleContext()) { var books = context.Books .FromSql("EXEC GetAllBooks") .ToList(); } My understanding is a DbSet represents an table. Note that I am working against an existing DB

问题 I am trying to join two tables in EntityFramework Core using linq syntax in the following way: var results = dc.EntityA.Join(dc.EntityB, a => a.StringProperty, b => b.StringProperty, (a, b) => DoSomeStuff(a, b)).ToList(); Where StringProperty is a string column in the database. I am getting the error {"Invalid column name 'EntityId'."} I found this similar question Entity Framework: Invalid column name 'OrganizationStructure_ID' where it is suggested to set the foreignkeys during

问题 My goal is async loading of related entities using DBContext. Let imagine two projects. The first named MyApp.Domain and contains domain entities. namespace MyApp.Domain { public class PlanPage { public Guid Id { get; set; } } } namespace MyApp.Domain { public class PlanPageDay { public Guid Id { get; set; } public Guid PlanPageId { get; set; } } } The second project named MyApp.Infrastructure.EntityFramework and contains configuration of projection entities to database. It also contains

问题 Is there any possible way to create migration on runtime in efcore. context.Database.Migrate(); Before this code, I need a code that, when I started my app, should create a migration about diff between postgresql database tables and ef models. Is there any way to do this? PM> enable-migrations PM> add-migration initial PM> update-database I dont want to use these ones. I want to make these code's jobs on runtime. I hope I could explain myself clearly. 回答1: Note, you need to re-compile the app

问题 This is the first time I have attempted to join information from one database to the other. I have a accounting database and a regular site database. Trying to keep them separate. I have a page that shows Transactions but am getting the information for a few of the columns from the regular database by way of Id's. Below is my Model. I am showing nothing in the fields for the items in the other database. public class Transaction { [Key] public Guid TransactionId { get; set; } public string

问题 I am trying to use an existing library which is a .net library which uses EF 6.0 to connect to a database. Since Azure Functions does not have an app.config file, I am trying to set the connection string using C# code. But I am getting the following exception while connecting to the DB using my DB context: System.ArgumentException: The ADO.NET provider with invariant name 'System.Data.SqlClient' is either not registered in the machine or application config file, or could not be loaded. See

问题 I have a simple C# console application and its code is like this: using System; using System.Collections.Generic; using System.Data; using System.Data.Common; using System.Linq; using System.Text; using System.Threading.Tasks; using Oracle.ManagedDataAccess.Client; namespace ConsoleApp1 { class Program { static void Main(string[] args) { SHRSContext shrsContext = new SHRSContext(); DbCommand cmd = shrsContext.Database.Connection.CreateCommand(); cmd.CommandText = "PKG_SHRS.GETLOGINATTEMPT";

问题 I am struggling with using multiple dbContext with an single web application in ASP.NET MVC 5. I am following code First existing database design approach. i need guideline how to do that say in example if i am creating 5 models using ADO.NET, it will create 5 dbContext along with its model classes. how it will change in web.config file? Many Thanks public partial class DefaultContext : DbContext { public DefaultContext() : base("name=DefaultContext") { } protected override void

问题 I am using Entity Framework 6.0 with Microsoft SQL Server. By default, the primary key it generates for a table is named like PK_dbo.TableName , where TableName is in a plural form, even though the actual name of the table is in a singular form. For example, I have a table named dbo.Employee . Yet the primary key denoted by EF 6 is PK_dbo.Employees . Is there any way to change the primary key to something like PK_TableName where the TableName is in a singular form? Update: Thanks for the