代码优先：将实体映射到现有的数据库表 [英] Code-first: Mapping entities to existing database tables

问题描述

通常情况下，我将使用数据库 - 数据库，第一种方法和我的实体和上下文代码生成，但使用设计师已经成为一个巨大的痛苦。

我已经设置了Database.SetInitializer（null），因为我不希望EF更改我的模式。

数据库架构

代码优先：

 code> public class Project 
 {
 public int ProjectId {get;组; } 
 
 public string Name {get;组; } 
 
 public string描述{get;组; 
 
 
 public class ReleaseControlContext：DbContext 
 {
 public ReleaseControlContext（）
：base（ConfigurationManager.ConnectionStrings [ReleaseControl]。ConnectionString） 
 {
 Database.SetInitializer< ReleaseControlContext>（null）; 
} 
 
 public DbSet< Project>项目{get;组; } 
} 
  

致电代码

  using（var context = new ReleaseControlContext（））
 {
 var projects = context.Projects.ToList（）; 
} 
  

抛出以下异常：

SqlException：无效的对象名称'dbo.Projects'。

这是因为我的数据库表是项目而不是项目。我不想将我的上下文的 DbSet< Project> 重命名为Project，因为这在语义上是不正确的。

问题：

我必须使用流畅的API /数据注释来在项目数据库之间进行映射表和 DbSet< Project>项目集合？

解决方案

您可以使用

  [Table（Project）] 
 public class Project {
 .... 
} 
  

对项目实体的注释，或$ OnModelCreating（DbModelBuilder modelBuilder）调用 modelBuilder.Entity< Project>（）。ToTable（Project）; 。

同样的事情。

I am using Entity Framework 6 code-first with an existing database, but having problems mapping my entities to the database tables.

Normally, I would use database-first approach and have my entity and context code generated, but using the designer has become a huge pain.

I have set Database.SetInitializer(null) as I do not want EF to change my schema.

Database schema:

Code-first:

public class Project
{
    public int ProjectId { get; set; }

    public string Name { get; set; }

    public string Description { get; set; }
}

public class ReleaseControlContext : DbContext
{
    public ReleaseControlContext()
        : base(ConfigurationManager.ConnectionStrings["ReleaseControl"].ConnectionString) 
    {
        Database.SetInitializer<ReleaseControlContext>(null);
    }

    public DbSet<Project> Projects { get; set; }
}

Calling code:

using(var context = new ReleaseControlContext())
{
    var projects = context.Projects.ToList();
}

The following exception is thrown:

SqlException: Invalid object name 'dbo.Projects'.

This is because my database table is Project and not Projects. I don't want to rename my context's DbSet<Project> to "Project" because that would be semantically incorrect.

Question:

Do I have to use the fluent API/data annotations to map between the Project database table and the DbSet<Project> Projects collection?

解决方案

You can use the

[Table("Project")] 
public class Project {
....
}

annotation against the Project entity, or in the OnModelCreating(DbModelBuilder modelBuilder) you can call modelBuilder.Entity<Project>().ToTable("Project");.

Both would do the same thing.

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