由于实体无法删除约束，因此无法更新数据库 [英] Cannot update database because entity cannot drop constraint

问题描述

我创建了一些新表，我发现我没有对id使用好的命名约定。

I created some new tables and I noticed I didn't use the good naming convention for the ids.

所以我做了一个新的使用新ID的add-migration ，但是当我尝试更新数据库时，出现以下错误：

So I did a new add-migration with the new ids but when I try to update-database I have the following error :

表
'AspNetUsers'正在引用约束'PK_dbo.DB_User_Type'，外键约束
'FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_Type_Id'。无法删除
约束。请参阅先前的错误。

The constraint 'PK_dbo.DB_User_Type' is being referenced by table 'AspNetUsers', foreign key constraint 'FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_Type_Id'. Could not drop constraint. See previous errors.

我不明白，因为脚本首先删除所有约束。

I don't understand because the script starts by dropping all constraints.

有人可以解释如何解决此错误吗？

Could someone explain how to solve this error please?

我正在使用新方法<$ c首先从现有数据库中的$ c>代码。这是 Up 函数

I'm using the new approach code first from an existing database from entity 6.1. Here is the Up function

public override void Up()
        {
            DropForeignKey("dbo.DB_Company_Profile", "DB_Category_Id", "dbo.DB_Category");
            DropForeignKey("dbo.DB_Category_Translation", "DB_Category_Id", "dbo.DB_Category");
            DropForeignKey("dbo.DB_User_Type_Translation", "DB_User_Type_Id", "dbo.DB_User_Type");
            DropForeignKey("dbo.DB_Company_Profile", "category_id", "dbo.DB_Category");
            DropForeignKey("dbo.DB_Category_Translation", "category_id", "dbo.DB_Category");
            DropForeignKey("dbo.AspNetUsers", "DB_User_Type_user_type_id", "dbo.DB_User_Type");
            DropForeignKey("dbo.DB_User_Type_Translation", "user_type_id", "dbo.DB_User_Type");
            DropIndex("dbo.DB_Company_Profile", new[] { "DB_Category_Id" });
            DropIndex("dbo.DB_Category_Translation", new[] { "DB_Category_Id" });
            DropIndex("dbo.DB_User_Type_Translation", new[] { "DB_User_Type_Id" });
            DropColumn("dbo.DB_Company_Profile", "category_id");
            DropColumn("dbo.DB_Category_Translation", "category_id");
            DropColumn("dbo.DB_User_Type_Translation", "user_type_id");
            RenameColumn(table: "dbo.AspNetUsers", name: "DB_User_Type_Id", newName: "DB_User_Type_user_type_id");
            RenameColumn(table: "dbo.DB_Company_Profile", name: "DB_Category_Id", newName: "category_id");
            RenameColumn(table: "dbo.DB_Category_Translation", name: "DB_Category_Id", newName: "category_id");
            RenameColumn(table: "dbo.DB_User_Type_Translation", name: "DB_User_Type_Id", newName: "user_type_id");
            RenameIndex(table: "dbo.AspNetUsers", name: "IX_DB_User_Type_Id", newName: "IX_DB_User_Type_user_type_id");
            DropPrimaryKey("dbo.DB_Category");
            DropPrimaryKey("dbo.DB_User_Type");
            AddColumn("dbo.DB_Category", "category_id", c => c.Int(nullable: false, identity: true));
            AddColumn("dbo.DB_User_Type", "user_type_id", c => c.Int(nullable: false, identity: true));
            AlterColumn("dbo.DB_Company_Profile", "category_id", c => c.Int(nullable: false));
            AlterColumn("dbo.DB_Category_Translation", "category_id", c => c.Int(nullable: false));
            AlterColumn("dbo.DB_User_Type_Translation", "user_type_id", c => c.Int(nullable: false));
            AddPrimaryKey("dbo.DB_Category", "category_id");
            AddPrimaryKey("dbo.DB_User_Type", "user_type_id");
            CreateIndex("dbo.DB_Company_Profile", "category_id");
            CreateIndex("dbo.DB_Category_Translation", "category_id");
            CreateIndex("dbo.DB_User_Type_Translation", "user_type_id");
            AddForeignKey("dbo.DB_Company_Profile", "category_id", "dbo.DB_Category", "category_id", cascadeDelete: true);
            AddForeignKey("dbo.DB_Category_Translation", "category_id", "dbo.DB_Category", "category_id", cascadeDelete: true);
            AddForeignKey("dbo.DB_User_Type_Translation", "user_type_id", "dbo.DB_User_Type", "user_type_id", cascadeDelete: true);
            AddForeignKey("dbo.AspNetUsers", "DB_User_Type_user_type_id", "dbo.DB_User_Type", "user_type_id");
            DropColumn("dbo.DB_Category", "Id");
            DropColumn("dbo.DB_User_Type", "Id");
        }

推荐答案

我必须删除外文在运行 update-database 命令之前，请先手动输入密钥。因为我数据库中的约束名称类似于： FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_TypeId

I had to delete the foreign key manually before running the update-database command. Because the constraint name in my DB is something like: FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_TypeId

而约束脚本是尝试删除的是：
FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_Type_Id

While the constraint the script is trying to drop is: FK_dbo.AspNetUsers_dbo.DB_User_Type_DB_User_Type_Id

这篇关于由于实体无法删除约束，因此无法更新数据库的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！