asp.net-core - Code First 中的 Identity 和 Mysql - 指定的键太长；最大 key 长度为 1000 字节

Question

我正在尝试使用 MySQL 驱动程序创建带有 IentityCore 的 CodeFirst 数据库。

我的 用户 DbModel 是这样的——

[Table("User")]
public class User : IdentityUser<int>
{
    public string Name { get; set; }
    public string Password { get; set; }
}

和 角色 DBModel 是这样的——

[Table("Role")]
public class Role : IdentityRole<int>
{
    public string Description { get; set; }
}

我的 DbContext 是这样的-

public class InventoryManagementDbContext : IdentityDbContext<User, Role, int>
{
    //Table List
    public DbSet<Employee> Employies { get; set; }
    public DbSet<ProductCategory> ProductCategorys { get; set; }
    public DbSet<ProductType> ProductTypes { get; set; }
    public DbSet<Product> Products { get; set; }
    public DbSet<Entry> Entries { get; set; }
    public DbSet<Exit> Exits { get; set; }
    //Table List End

    public InventoryManagementDbContext(DbContextOptions<InventoryManagementDbContext> options)
    : base(options)
    {}

    //Fluent API to make Composite Key
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        // email address doesn't need to be in unicode, check it spec
        modelBuilder.Entity<User>().Property(u => u.UserName).IsUnicode(false);
        modelBuilder.Entity<User>().Property(u => u.Email).IsUnicode(false);
        modelBuilder.Entity<Role>().Property(r => r.Name).HasMaxLength(255);
    }
}

因此，我为电子邮件和用户名禁用了 Unicode，并为 设置了 MaxLength角色名称 .

仍然如果我试图执行这个命令 -

Add-Migration

然后我收到此错误-

.....................................
.....................................

fail: Microsoft.EntityFrameworkCore.Database.Command[20102]
      Failed executing DbCommand (13ms) [Parameters=[], CommandType='Text', CommandTimeout='60']
      CREATE TABLE `AspNetUserLogins` (
          `LoginProvider` varchar(767) NOT NULL,
          `ProviderKey` varchar(767) NOT NULL,
          `ProviderDisplayName` text NULL,
          `UserId` int NOT NULL,
          PRIMARY KEY (`LoginProvider`, `ProviderKey`),
          CONSTRAINT `FK_AspNetUserLogins_AspNetUsers_UserId` FOREIGN KEY (`UserId`) REFERENCES `AspNetUsers` (`Id`) ON DELETE CASCADE
      );
MySql.Data.MySqlClient.MySqlException (0x80004005): Specified key was too long; max key length is 1000 bytes
   at MySql.Data.MySqlClient.MySqlStream.ReadPacket()
   at MySql.Data.MySqlClient.NativeDriver.GetResult(Int32& affectedRow, Int64& insertedId)
   at MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId, Boolean force)
   at MySql.Data.MySqlClient.MySqlDataReader.NextResult()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()
   at System.Data.Common.DbCommand.ExecuteNonQueryAsync(CancellationToken cancellationToken)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.<ExecuteAsync>d__17.MoveNext()
failverbose: Found DbContext 'InventoryManagementDbContext'.
: Microsoft.EntityFrameworkCore.Database.Command[20102]
      Failed executing DbCommand (13ms) [Parameters=[], CommandType='Text', CommandTimeout='60']
      CREATE TABLE `AspNetUserLogins` (
          `LoginProvider` varchar(767) NOT NULL,
          `ProviderKey` varchar(767) NOT NULL,
          `ProviderDisplayName` text NULL,
          `UserId` int NOT NULL,
          PRIMARY KEY (`LoginProvider`, `ProviderKey`),
          CONSTRAINT `FK_AspNetUserLogins_AspNetUsers_UserId` FOREIGN KEY (`UserId`) REFERENCES `AspNetUsers` (`Id`) ON DELETE CASCADE
      );
MySql.Data.MySqlClient.MySqlException (0x80004005): Specified key was too long; max key length is 1000 bytes
   at MySql.Data.MySqlClient.MySqlStream.ReadPacket()
   at MySql.Data.MySqlClient.NativeDriver.GetResult(Int32& affectedRow, Int64& insertedId)
   at MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId, Boolean force)
   at MySql.Data.MySqlClient.MySqlDataReader.NextResult()
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()
   at System.Data.Common.DbCommand.ExecuteNonQueryAsync(CancellationToken cancellationToken)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.<ExecuteAsync>d__17.MoveNext()
Microsoft.EntityFrameworkCore.Infrastructure[10403]
      Entity Framework Core 2.0.2-rtm-10011 initialized 'InventoryManagementDbContext' using provider 'MySql.Data.EntityFrameworkCore' with options: NoTracking CommandTimeout=60 
Microsoft.EntityFrameworkCore.Infrastructure[10403]
      Entity Framework Core 2.0.2-rtm-10011 initialized 'InventoryManagementDbContext' using provider 'MySql.Data.EntityFrameworkCore' with options: NoTracking CommandTimeout=60

我的完整代码可以在 中找到here .

有人可以帮忙吗？

关于-

This question没有解决我的问题，因为我没有遇到 General Keys 的任何问题，它们非常适合我。

我在尝试使用时遇到问题 Identity .

Answer 1

对于任何有同样问题的人，即使问题已经有一段时间了，我也会把它留在这里。

您需要为以下几个属性设置最大长度:

身份角色

身份用户

身份用户登录

IdentityUserToken

在本例中，您扩展了类 IdentityUser和 IdentityRole使用 integer PK，所以你的代码，使用 fluent API，应该是这样的:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    int stringMaxLength = /* something like 100*/;
    // User IdentityRole and IdentityUser in case you haven't extended those classes
    builder.Entity<Role>(x => x.Property(m => m.Name).HasMaxLength(stringMaxLength));
    builder.Entity<Role>(x => x.Property(m => m.NormalizedName).HasMaxLength(stringMaxLength));
    builder.Entity<User>(x => x.Property(m => m.NormalizedUserName).HasMaxLength(stringMaxLength));

    // We are using int here because of the change on the PK
    builder.Entity<IdentityUserLogin<int>>(x => x.Property(m => m.LoginProvider).HasMaxLength(stringMaxLength));
    builder.Entity<IdentityUserLogin<int>>(x => x.Property(m => m.ProviderKey).HasMaxLength(stringMaxLength));

    // We are using int here because of the change on the PK
    builder.Entity<IdentityUserToken<int>>(x => x.Property(m => m.LoginProvider).HasMaxLength(stringMaxLength));
    builder.Entity<IdentityUserToken<int>>(x => x.Property(m => m.Name).HasMaxLength(stringMaxLength));

   // etc..

希望能帮助到你!