身份entity framework库 – 更新数据库

我刚刚将库Microsoft.AspNet.Identity.EntityFramework更新到最后一个版本（2.0.0.0），我发现创建表时出现了一些错误。 当我生成迁移代码（向上和向下方法）时，我无法将更改上传到数据库因为我执行“Updata-Database”时索引有问题

指定密钥太长; 最大密钥长度为767字节

要执行的代码：

public override void Up() { CreateTable( "dbo.AspNetRoles", c => new { Id = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), Name = c.String(nullable: false, maxLength: 256, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id) .Index(t => t.Name, unique: true, name: "RoleNameIndex"); CreateTable( "dbo.AspNetUserRoles", c => new { UserId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), RoleId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => new { t.UserId, t.RoleId }) .ForeignKey("dbo.AspNetRoles", t => t.RoleId, cascadeDelete: true) .ForeignKey("dbo.AspNetUsers", t => t.UserId, cascadeDelete: true) .Index(t => t.UserId) .Index(t => t.RoleId); CreateTable( "dbo.AspNetUsers", c => new { Id = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), Email = c.String(maxLength: 256, storeType: "nvarchar"), EmailConfirmed = c.Boolean(nullable: false), PasswordHash = c.String(maxLength: 256, storeType: "nvarchar"), SecurityStamp = c.String(maxLength: 256, storeType: "nvarchar"), PhoneNumber = c.String(maxLength: 256, storeType: "nvarchar"), PhoneNumberConfirmed = c.Boolean(nullable: false), TwoFactorEnabled = c.Boolean(nullable: false), LockoutEndDateUtc = c.DateTime(precision: 0), LockoutEnabled = c.Boolean(nullable: false), AccessFailedCount = c.Int(nullable: false), UserName = c.String(nullable: false, maxLength: 256, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id) .Index(t => t.UserName, unique: true, name: "UserNameIndex"); CreateTable( "dbo.AspNetUserClaims", c => new { Id = c.Int(nullable: false, identity: true), UserId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), ClaimType = c.String(maxLength: 256, storeType: "nvarchar"), ClaimValue = c.String(maxLength: 256, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id) .ForeignKey("dbo.AspNetUsers", t => t.UserId, cascadeDelete: true) .Index(t => t.UserId); CreateTable( "dbo.AspNetUserLogins", c => new { LoginProvider = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), ProviderKey = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), UserId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => new { t.LoginProvider, t.ProviderKey, t.UserId }) .ForeignKey("dbo.AspNetUsers", t => t.UserId, cascadeDelete: true) .Index(t => t.UserId); } public override void Down() { DropForeignKey("dbo.AspNetUserRoles", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserLogins", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserClaims", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserRoles", "RoleId", "dbo.AspNetRoles"); DropIndex("dbo.AspNetUserLogins", new[] { "UserId" }); DropIndex("dbo.AspNetUserClaims", new[] { "UserId" }); DropIndex("dbo.AspNetUsers", "UserNameIndex"); DropIndex("dbo.AspNetUserRoles", new[] { "RoleId" }); DropIndex("dbo.AspNetUserRoles", new[] { "UserId" }); DropIndex("dbo.AspNetRoles", "RoleNameIndex"); DropTable("dbo.AspNetUserLogins"); DropTable("dbo.AspNetUserClaims"); DropTable("dbo.AspNetUsers"); DropTable("dbo.AspNetUserRoles"); DropTable("dbo.AspNetRoles"); } 

当我使用Microsoft.AspNet.Identity.EntityFramework的versión1.0.0.0时，更新数据库的代码是不同的，我没有任何问题

 public override void Up() { CreateTable( "dbo.AspNetRoles", c => new { Id = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), Name = c.String(nullable: false, maxLength: 256, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id); CreateTable( "dbo.AspNetUsers", c => new { Id = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), UserName = c.String(maxLength: 256, storeType: "nvarchar"), PasswordHash = c.String(maxLength: 256, storeType: "nvarchar"), SecurityStamp = c.String(maxLength: 256, storeType: "nvarchar"), Discriminator = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id); CreateTable( "dbo.AspNetUserClaims", c => new { Id = c.Int(nullable: false, identity: true), ClaimType = c.String(maxLength: 256, storeType: "nvarchar"), ClaimValue = c.String(maxLength: 256, storeType: "nvarchar"), User_Id = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => t.Id) .ForeignKey("dbo.AspNetUsers", t => t.User_Id, cascadeDelete: true) .Index(t => t.User_Id); CreateTable( "dbo.AspNetUserLogins", c => new { UserId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), LoginProvider = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), ProviderKey = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => new { t.UserId, t.LoginProvider, t.ProviderKey }) .ForeignKey("dbo.AspNetUsers", t => t.UserId, cascadeDelete: true) .Index(t => t.UserId); CreateTable( "dbo.AspNetUserRoles", c => new { UserId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), RoleId = c.String(nullable: false, maxLength: 128, storeType: "nvarchar"), }) .PrimaryKey(t => new { t.UserId, t.RoleId }) .ForeignKey("dbo.AspNetRoles", t => t.RoleId, cascadeDelete: true) .ForeignKey("dbo.AspNetUsers", t => t.UserId, cascadeDelete: true) .Index(t => t.UserId) .Index(t => t.RoleId); } public override void Down() { DropForeignKey("dbo.AspNetUserRoles", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserLogins", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserClaims", "UserId", "dbo.AspNetUsers"); DropForeignKey("dbo.AspNetUserRoles", "RoleId", "dbo.AspNetRoles"); DropIndex("dbo.AspNetUserLogins", new[] { "UserId" }); DropIndex("dbo.AspNetUserClaims", new[] { "UserId" }); DropIndex("dbo.AspNetUsers", "UserNameIndex"); DropIndex("dbo.AspNetUserRoles", new[] { "RoleId" }); DropIndex("dbo.AspNetUserRoles", new[] { "UserId" }); DropIndex("dbo.AspNetRoles", "RoleNameIndex"); DropTable("dbo.AspNetUserLogins"); DropTable("dbo.AspNetUserClaims"); DropTable("dbo.AspNetUsers"); DropTable("dbo.AspNetUserRoles"); DropTable("dbo.AspNetRoles"); } 

任何人都可以帮助我尝试解决问题吗？

提前致谢！！

Answer 1

您可能需要查看本教程： http ： //www.asp.net/mvc/tutorials/security/aspnet-identity-using-mysql-storage-with-an-entityframework-mysql-provider – 特别是“添加”部分自定义MigrationHistory上下文“，它解释了如何设置自定义HistoryContext以解决主键大小问题。

Answer 2

我知道这是一个老post，但我今天遇到了同样的问题并对此进行了一些调查，并希望分享我的发现和解决方案。

问题是Microsoft在版本之间为AspNetRoles的Name列添加了一个唯一索引，并且由于此列的大小为256，因此它破坏了MySql的索引规则。 AspNetUsers上的Name列上也会出现此问题。

所以，我去分析如何解决这个问题，我认为最正确的做法是减少Name列的长度（恕我直言，这真的没有任何理由让一个角色/用户的名字很长）。

在调查IdentityDbContext（这是基类）上的代码后，我认为解决此问题的最正确方法是覆盖ApplicationDbContext的OnModelCreating并调整列大小，如下所示：

 public class ApplicationDbContext : IdentityDbContext { //... default code for ApplicationDbContext protected override void OnModelCreating(DbModelBuilder modelBuilder) { if (modelBuilder == null) { throw new ArgumentNullException("modelBuilder"); } base.OnModelCreating(modelBuilder); modelBuilder.Entity().Property(u => u.UserName).HasMaxLength(128); //Uncomment this to have Email length 128 too (not neccessary) //modelBuilder.Entity().Property(u => u.Email).HasMaxLength(128); modelBuilder.Entity().Property(r => r.Name).HasMaxLength(128); } } 

此代码将使用base.OnModelCreating调用使用默认配置初始化标识模型，然后使用我们自己的调用覆盖基类中完成的设置。

由于您要创建迁移项目，因此您需要重新运行迁移创建以获取更新的模型（或手动修改模型以调整列大小）。

这将解决问题，您将拥有Asp.NET Identity系统的全部function。

当然，为了在创建项目时不会出现任何错误，您只需修改迁移代码，但随后您将与您的上下文定义的模型有所不同，这可能会导致问题。

Answer 3

这可能是由于您的数据库使用UTF8排序规则。

解决此问题的一种可能方法是将包含maxLength: 256的代码的所有部分更改为maxLength: 190 。

另一种方法是将数据库上的UTF8排序规则更改为latin1或类似的排序规则。