实体框架迁移重命名表和列

Question

我重命名了一对夫妇实体及其导航属性，并在EF 5中生成了新的迁移。与EF迁移中的重命名一样，默认情况下，它将删除对象并重新创建它们。这不是我想要的，所以我几乎必须从头开始构建迁移文件。

public override void Up() 
    { 
     DropForeignKey("dbo.ReportSectionGroups", "Report_Id", "dbo.Reports"); 
     DropForeignKey("dbo.ReportSections", "Group_Id", "dbo.ReportSectionGroups"); 
     DropForeignKey("dbo.Editables", "Section_Id", "dbo.ReportSections"); 
     DropIndex("dbo.ReportSectionGroups", new[] { "Report_Id" }); 
     DropIndex("dbo.ReportSections", new[] { "Group_Id" }); 
     DropIndex("dbo.Editables", new[] { "Section_Id" }); 

     RenameTable("dbo.ReportSections", "dbo.ReportPages"); 
     RenameTable("dbo.ReportSectionGroups", "dbo.ReportSections"); 
     RenameColumn("dbo.ReportPages", "Group_Id", "Section_Id"); 

     AddForeignKey("dbo.ReportSections", "Report_Id", "dbo.Reports", "Id"); 
     AddForeignKey("dbo.ReportPages", "Section_Id", "dbo.ReportSections", "Id"); 
     AddForeignKey("dbo.Editables", "Page_Id", "dbo.ReportPages", "Id"); 
     CreateIndex("dbo.ReportSections", "Report_Id"); 
     CreateIndex("dbo.ReportPages", "Section_Id"); 
     CreateIndex("dbo.Editables", "Page_Id"); 
    } 

    public override void Down() 
    { 
     DropIndex("dbo.Editables", "Page_Id"); 
     DropIndex("dbo.ReportPages", "Section_Id"); 
     DropIndex("dbo.ReportSections", "Report_Id"); 
     DropForeignKey("dbo.Editables", "Page_Id", "dbo.ReportPages"); 
     DropForeignKey("dbo.ReportPages", "Section_Id", "dbo.ReportSections"); 
     DropForeignKey("dbo.ReportSections", "Report_Id", "dbo.Reports"); 

     RenameColumn("dbo.ReportPages", "Section_Id", "Group_Id"); 
     RenameTable("dbo.ReportSections", "dbo.ReportSectionGroups"); 
     RenameTable("dbo.ReportPages", "dbo.ReportSections"); 

     CreateIndex("dbo.Editables", "Section_Id"); 
     CreateIndex("dbo.ReportSections", "Group_Id"); 
     CreateIndex("dbo.ReportSectionGroups", "Report_Id"); 
     AddForeignKey("dbo.Editables", "Section_Id", "dbo.ReportSections", "Id"); 
     AddForeignKey("dbo.ReportSections", "Group_Id", "dbo.ReportSectionGroups", "Id"); 
     AddForeignKey("dbo.ReportSectionGroups", "Report_Id", "dbo.Reports", "Id"); 
    } 

所有我想要做的是重新命名dbo.ReportSections到dbo.ReportPages然后dbo.ReportSectionGroups到dbo.ReportSections。然后我需要将dbo.ReportPages的外键列从Group_Id重命名为Section_Id。

我在删除将表连接在一起的外键和索引，然后我重命名表和外键列，然后再次添加索引和外键。我认为这是工作，但我得到一个SQL错误。

消息15248，级别11，状态1，过程sp_rename可以，215线 要么参数@objname不明确或所要求保护的@objtype（列）是错误的。 Msg 4902，Level 16，State 1，Line 10 找不到对象“dbo.ReportSections”，因为它不存在或您没有权限。

我没有一个容易的时间搞清楚这里有什么问题。任何见解都将非常有帮助。

Answer 1

没关系。我正在使这种方式比它真正需要的更复杂。

这就是我所需要的。重命名方法只会生成对系统存储过程的调用，我想这会处理所有事情，包括具有新列名称的外键。

public override void Up() 
{ 
    RenameTable("ReportSections", "ReportPages"); 
    RenameTable("ReportSectionGroups", "ReportSections"); 
    RenameColumn("ReportPages", "Group_Id", "Section_Id"); 
} 

public override void Down() 
{ 
    RenameColumn("ReportPages", "Section_Id", "Group_Id"); 
    RenameTable("ReportSections", "ReportSectionGroups"); 
    RenameTable("ReportPages", "ReportSections"); 
} 

Answer 2

我只是想在EF6相同（代码第一个实体命名）。我只是重命名了这个类，并使用包管理器控制台添加了一个迁移，并且使用RenameTable（...）进行迁移是我自动生成的。我不得不承认，我确信实体的唯一更改是重命名它，所以没有新列或重命名列，所以我不能确定这是EF6的事情还是只是EF（总是）能够检测到这种简单的迁移。

Answer 3

如果你不喜欢写/在迁移类手动更改所需的代码，你可以按照两步走的方法，其自动进行所需要的RenameColumn代码：

第一步使用ColumnAttribute引进新的列名，然后添加迁移（如Add-Migration ColumnChanged）

public class ReportPages 
{ 
    [Column("Section_Id")]     //Section_Id 
    public int Group_Id{get;set} 
} 

步骤二更改属性名称，然后再次申请同一迁移（如Add-Migration ColumnChanged）在Package Manager控制台

public class ReportPages 
{ 
    [Column("Section_Id")]     //Section_Id 
    public int Section_Id{get;set} 
} 

如果你看一下移民类，你可以看到生成的自动代码为RenameColumn。

Answer 4

要扩大一点Hossein Narimani Rad的答案，您可以使用系统重命名表和列。ComponentModel.DataAnnotations.Schema.TableAttribute和System.ComponentModel.DataAnnotations.Schema.ColumnAttribute。

这有几个好处：

1. 这不仅会自动创建该名称的迁移，但
2. 也会美味删除任何外键并重新创建它们对新表和列名，给予外键和合适的名字。
3. 所有这一切都不会丢失任何表中的数据

例如，添加[Table("Staffs")]：

[Table("Staffs")] 
public class AccountUser 
{ 
    public long Id { get; set; } 

    public long AccountId { get; set; } 

    public string ApplicationUserId { get; set; } 

    public virtual Account Account { get; set; } 

    public virtual ApplicationUser User { get; set; } 
} 

将生成的迁移：

protected override void Up(MigrationBuilder migrationBuilder) 
    { 
     migrationBuilder.DropForeignKey(
      name: "FK_AccountUsers_Accounts_AccountId", 
      table: "AccountUsers"); 

     migrationBuilder.DropForeignKey(
      name: "FK_AccountUsers_AspNetUsers_ApplicationUserId", 
      table: "AccountUsers"); 

     migrationBuilder.DropPrimaryKey(
      name: "PK_AccountUsers", 
      table: "AccountUsers"); 

     migrationBuilder.RenameTable(
      name: "AccountUsers", 
      newName: "Staffs"); 

     migrationBuilder.RenameIndex(
      name: "IX_AccountUsers_ApplicationUserId", 
      table: "Staffs", 
      newName: "IX_Staffs_ApplicationUserId"); 

     migrationBuilder.RenameIndex(
      name: "IX_AccountUsers_AccountId", 
      table: "Staffs", 
      newName: "IX_Staffs_AccountId"); 

     migrationBuilder.AddPrimaryKey(
      name: "PK_Staffs", 
      table: "Staffs", 
      column: "Id"); 

     migrationBuilder.AddForeignKey(
      name: "FK_Staffs_Accounts_AccountId", 
      table: "Staffs", 
      column: "AccountId", 
      principalTable: "Accounts", 
      principalColumn: "Id", 
      onDelete: ReferentialAction.Cascade); 

     migrationBuilder.AddForeignKey(
      name: "FK_Staffs_AspNetUsers_ApplicationUserId", 
      table: "Staffs", 
      column: "ApplicationUserId", 
      principalTable: "AspNetUsers", 
      principalColumn: "Id", 
      onDelete: ReferentialAction.Restrict); 
    } 

    protected override void Down(MigrationBuilder migrationBuilder) 
    { 
     migrationBuilder.DropForeignKey(
      name: "FK_Staffs_Accounts_AccountId", 
      table: "Staffs"); 

     migrationBuilder.DropForeignKey(
      name: "FK_Staffs_AspNetUsers_ApplicationUserId", 
      table: "Staffs"); 

     migrationBuilder.DropPrimaryKey(
      name: "PK_Staffs", 
      table: "Staffs"); 

     migrationBuilder.RenameTable(
      name: "Staffs", 
      newName: "AccountUsers"); 

     migrationBuilder.RenameIndex(
      name: "IX_Staffs_ApplicationUserId", 
      table: "AccountUsers", 
      newName: "IX_AccountUsers_ApplicationUserId"); 

     migrationBuilder.RenameIndex(
      name: "IX_Staffs_AccountId", 
      table: "AccountUsers", 
      newName: "IX_AccountUsers_AccountId"); 

     migrationBuilder.AddPrimaryKey(
      name: "PK_AccountUsers", 
      table: "AccountUsers", 
      column: "Id"); 

     migrationBuilder.AddForeignKey(
      name: "FK_AccountUsers_Accounts_AccountId", 
      table: "AccountUsers", 
      column: "AccountId", 
      principalTable: "Accounts", 
      principalColumn: "Id", 
      onDelete: ReferentialAction.Cascade); 

     migrationBuilder.AddForeignKey(
      name: "FK_AccountUsers_AspNetUsers_ApplicationUserId", 
      table: "AccountUsers", 
      column: "ApplicationUserId", 
      principalTable: "AspNetUsers", 
      principalColumn: "Id", 
      onDelete: ReferentialAction.Restrict); 
    }