实体框架迁移重命名表和列

问题描述 投票：87回答：6

我重命名了几个实体及其导航属性，并在EF 5中生成了一个新的迁移。通常在EF迁移中重命名，默认情况下它会删除对象并重新创建它们。这不是我想要的，所以我几乎不得不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");
    }

我所要做的就是将dbo.ReportSections重命名为dbo.ReportPages，然后将dbo.ReportSectionGroups重命名为dbo.ReportSections。然后我需要将dbo.ReportPages上的外键列从Group_Id重命名为Section_Id。

我正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，然后我再次添加索引和外键。我以为这会起作用，但我收到一个SQL错误。

消息15248，级别11，状态1，过程sp_rename，行215参数@objname不明确或声明的@objtype（COLUMN）错误。消息4902，级别16，状态1，行10无法找到对象“dbo.ReportSections”，因为它不存在或您没有权限。

我不是很容易弄清楚这里有什么问题。任何见解都会非常有帮助。

c# sql-server entity-framework entity-framework-5 ef-migrations
6个回答
125
投票

没关系。我这样做比实际需要的更复杂。

这就是我所需要的一切。重命名方法只是生成对sp_rename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");
}
32
投票

如果您不喜欢手动编写/更改Migration类中所需的代码，可以按照两步方法自动生成所需的RenameColumn代码：

第一步使用ColumnAttribute引入新的列名，然后添加迁移（例如Add-Migration ColumnChanged）

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

第二步更改属性名称，并再次应用于程序包管理器控制台中的相同迁移（例如Add-Migration ColumnChanged -force）

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

如果查看Migration类，可以看到生成的自动代码是RenameColumn。

11
投票

为了扩展Hossein Narimani Rad的答案，您可以分别使用System.ComponentModel.DataAnnotations.Schema.TableAttribute和System.ComponentModel.DataAnnotations.Schema.ColumnAttribute重命名表和列。

这有几个好处：

  1. 这不仅会自动创建名称迁移，而且
  2. 它还可以美味地删除任何外键并根据新的表和列名称重新创建它们，为外键和constaints提供正确的名称。
  3. 所有这些都不会丢失任何表数据

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);
    }
6
投票

在EF Core（2.0）中，我使用以下语句重命名表和列：

至于重命名表：

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.RenameTable(name: "OldTableName", schema: "dbo", newName: "NewTableName", newSchema: "dbo");
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.RenameTable(name: "NewTableName", schema: "dbo", newName: "OldTableName", newSchema: "dbo");
    }

至于重命名列：

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.RenameColumn(name: "OldColumnName", table: "TableName", newName: "NewColumnName", schema: "dbo");
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.RenameColumn(name: "NewColumnName", table: "TableName", newName: "OldColumnName", schema: "dbo");
    }
2
投票

我在EF6（代码第一实体重命名）中尝试了相同的操作。我只是重命名了类并使用包管理器控制台添加了迁移，并且自动为我生成了使用RenameTable（...）的迁移。我必须承认，我确保对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的东西还是只是EF（总是）能够检测到这种简单的迁移。

0
投票

表名和列名可以指定为DbContext映射的一部分。然后在迁移中不需要这样做。

public class MyContext : DbContext
{
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Restaurant>()
            .HasMany(p => p.Cuisines)
            .WithMany(r => r.Restaurants)
            .Map(mc =>
            {
                mc.MapLeftKey("RestaurantId");
                mc.MapRightKey("CuisineId");
                mc.ToTable("RestaurantCuisines");
            });
     }
}
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