MySql.Data.MySqlClient.MySqlException:重复条目

Question

如何从这个自动脚手架中从.net标识代码获得重复的条目错误：

        public async Task<IActionResult> OnPostAsync(string returnUrl = null)
        {
            returnUrl = returnUrl ?? Url.Content("~/");
            if (ModelState.IsValid)
            {
                var user = new ApplicationUser {  UserName = Input.Email, Email = Input.Email };
                var result = await _userManager.CreateAsync(user, Input.Password);
                if (result.Succeeded)
                {
                    _logger.LogInformation("User created a new account with password.");

                    var code = await _userManager.GenerateEmailConfirmationTokenAsync(user);
                    var callbackUrl = Url.Page(
                        "/Account/ConfirmEmail",
                        pageHandler: null,
                        values: new { userId = user.Id, code = code },
                        protocol: Request.Scheme);

                    await _emailSender.SendEmailAsync(Input.Email, "Confirm your email",
                        $"Please confirm your account by <a href='{HtmlEncoder.Default.Encode(callbackUrl)}'>clicking here</a>.");

                    await _signInManager.SignInAsync(user, isPersistent: false);
                    return LocalRedirect(returnUrl);
                }
                foreach (var error in result.Errors)
                {
                    ModelState.AddModelError(string.Empty, error.Description);
                }
            }

            // If we got this far, something failed, redisplay form
            return Page();
        }

生成此堆栈跟踪：

Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware1执行请求时发生了未处理的异常。Microsoft.EntityFrameworkCore.DbUpdateException:更新条目时发生错误。有关详细信息，请参阅内部异常。对象状态)--从抛出异常的前一个位置开始的堆栈跟踪的结束--在System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot) --从在C:\projects\mysqlconnector\src\MySqlConnector\Core\ResultSet.cs:line 43中抛出异常的前一个位置的堆栈跟踪的结束--在C：\projects\mysqlconnector\src\MySqlConnector\Core\ResultSet.cs:line 43中--内部异常堆栈跟踪的结束--在MySql.Data.MySqlClient.MySqlDataReader。C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 81 at MySql.Data.MySqlClient.MySqlDataReader.ReadFirstResultSetAsync(IOBehavior ioBehavior中的.ActivateResultSet(ResultSet resultSet) )在C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 307 at MySql.Data.MySqlClient.MySqlDataReader.CreateAsync(MySqlCommand命令中，( C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 292 at MySqlConnector.Core.TextCommandExecutor.ExecuteReaderAsync(String commandText，MySqlParameterCollection parameterCollection，CommandBehavior behavior，IOBehavior ioBehavior，CancellationToken cancellationToken)中的CommandBehavior行为，ResultSetProtocol resultSetProtocol，IOBehavior ioBehavior)，在C:\projects\mysqlconnector\src\MySqlConnector\Core\TextCommandExecutor.cs:line 37中的Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.ExecuteAsync(IRelationalConnection连接中，cancellationToken CommandBehavior，en19#2参数，Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlExecutionStrategy.ExecuteAsyncTState,TResult at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(IReadOnlyList1 entriesToSave, CancellationToken cancellationToken) at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken) at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken) at Microsoft.AspNetCore.Identity.EntityFrameworkCore.UserStore9.CreateAsync(TUser user，CancellationToken CancellationToken at Chuchubi.Data.MultiTenant.TenantUserStore.CreateAsync(ApplicationUser user，CancellationToken cancellationToken( C:\Users\Dropbox\Code\chuchubi-backend\Chuchubi.Data\MultiTenant\TenantUserStore.cs:line 30 at Microsoft.AspNetCore.Identity.UserManager1.CreateAsync(TUser user) at Microsoft.AspNetCore.Identity.UserManager1.CreateAsync(TUser user)，(字符串密码)(在Chuchubi.Areas.Identity.Pages.Account.RegisterModel.OnPostAsync(String returnUrl)在C:\Users\Dropbox\Code\chuchubi-backend\Chuchubi\Areas\Identity\Pages\Account\Register.cshtml.cs:line 71中Microsoft.AspNetCore.Mvc.RazorPages.Internal.ExecutorFactory.GenericTaskHandlerMethod.ConvertT在Microsoft.AspNetCore.Mvc.RazorPages.Internal.ExecutorFactory.GenericTaskHandlerMethod.Execute(Object接收器，( Microsoft.AspNetCore.Mvc.RazorPages.Internal.PageActionInvoker.InvokeHandlerMethodAsync() at Microsoft.AspNetCore.Mvc.RazorPages.Internal.PageActionInvoker.InvokeNextPageFilterAsync() at Microsoft.AspNetCore.Mvc.RazorPages.Internal.PageActionInvoker.Rethrow(PageHandlerExecutedContext context)在Microsoft.AspNetCore.Mvc.RazorPages.Internal.PageActionInvoker.Next(State& next，范围和作用域，对象和状态，( Microsoft.AspNetCore.Mvc.RazorPages.Internal.PageActionInvoker.InvokeInnerFilterAsync() at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeNextResourceFilter() at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow(ResourceExecutedContext context)在Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next(State& next，范围和作用域，对象和状态，( Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeFilterPipelineAsync() at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeAsync() at Microsoft.AspNetCore.Builder.RouterMiddleware.Invoke(HttpContext httpContext) ( Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context) ( Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context) ( SaasKit.Multitenancy.Internal.TenantResolutionMiddleware1.Invoke(HttpContext context, ITenantResolver1 tenantResolver) ( Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context ))(在Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.MigrationsEndPointMiddleware.Invoke(HttpContext上下文( Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.DatabaseErrorPageMiddleware.Invoke(HttpContext httpContext) at Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore.DatabaseErrorPageMiddleware.Invoke(HttpContext httpContext( at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)信息: Microsoft.AspNetCore.Hosting.Internal.WebHost2

这是来自visual自动生成的代码。

编辑：

MySql版本详细信息：

'immediate_server_version', '999999'
'innodb_version', '8.0.16'
'original_server_version', '999999'
'protocol_version', '10'
'slave_type_conversions', ''
'tls_version', 'TLSv1,TLSv1.1,TLSv1.2'
'version', '8.0.16'
'version_comment', 'MySQL Community Server - GPL'
'version_compile_machine', 'x86_64'
'version_compile_os', 'Win64'
'version_compile_zlib', '1.2.11'

我的首席执行官：

    <PackageReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.2.0" PrivateAssets="All" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.2.4" />
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.2.3" />
    <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="2.2.0" />
    <PackageReference Include="Pomelo.EntityFrameworkCore.MySql.Design" Version="1.1.2" />
    <PackageReference Include="SaasKit.Multitenancy" Version="1.1.4" />

这是在一个空数据库上完成的，在错误发生后，数据库中没有用户被插入！

Answer 1

好的，试图在一个干净的项目中复制这一点，我设法弄清楚了。因此，应用程序是多租户的，每个身份用户都与租户有一对一的关系。

使用SaasKit I将数据库模型租户缓存到内存中，同时创建如下所示的新用户：

IdentityUser.Tenant = cachedTenant;
DbContext.SaveChanges();

Entityframework将租户视为一个新的租户(未被跟踪)，从而导致重复消息。

所以重复的消息实际上是给新租户的。

通过缓存“视图模型”而不是数据库模型来修正。