System.MissingMethodException: 未找到方法：'UInt32 Npgsql.NpgsqlStatement.get_Rows()

Question

从今天早上开始，当我在数据库中更新或插入任何内容时出现此错误。这没有任何问题。找不到任何解决方法。

Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while updating the entries. See the inner exception for details. ---> System.MissingMethodException: Method not found: 'UInt32 Npgsql.NpgsqlStatement.get_Rows()'.
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch.Consume(RelationalDataReader reader)
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.Execute(IRelationalConnection connection)
   --- End of inner exception stack trace ---
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.Execute(IRelationalConnection connection)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.Execute(DbContext _, ValueTuple`2 parameters)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded) in C:\projects\EFCore.PG\src\EFCore.PG\Storage\Internal\NpgsqlExecutionStrategy.cs:line 51
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.Execute(IEnumerable`1 commandBatches, IRelationalConnection connection)
   at Microsoft.EntityFrameworkCore.Storage.RelationalDatabase.SaveChanges(IReadOnlyList`1 entries)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(IReadOnlyList`1 entriesToSave)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChanges(Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChanges()
   at App.Controllers.HomeController.NeuerEintrag(TelefonListe neuerEintrag) in D:\App\Controllers\HomeController.cs:line 128
   at lambda_method(Closure , Object , Object[] )
   at Microsoft.Extensions.Internal.ObjectMethodExecutor.Execute(Object target, Object[] parameters)
   at Microsoft.AspNetCore.Mvc.Internal.ActionMethodExecutor.SyncActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeActionMethodAsync()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeNextActionFilterAsync()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ActionExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeInnerFilterAsync()
   at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeNextResourceFilter()
   at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow(ResourceExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeFilterPipelineAsync()
   at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeAsync()
   at Microsoft.AspNetCore.Builder.RouterMiddleware.Invoke(HttpContext httpContext)
   at Microsoft.AspNetCore.Localization.RequestLocalizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Builder.RouterMiddleware.Invoke(HttpContext httpContext)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
Ausnahme ausgelöst: "System.NotImplementedException" in System.Private.CoreLib.dll
Ausnahme ausgelöst: "System.NotImplementedException" in System.Private.CoreLib.dll
Microsoft.AspNetCore.Hosting.Internal.WebHost:Information: Request finished in 600.8631ms 500 text/html; charset=utf-8
Der Thread 0x2bac hat mit Code 0 (0x0) geendet.
Der Thread 0x1b8 hat mit Code 0 (0x0) geendet.
Das Programm "[11660] dotnet.exe" wurde mit Code -1 (0xffffffff) beendet.

Answer 1

您可能已升级到新的 Npgsql 4.1.0，同时保留 EF Core 2.2 - 不幸的是，一项重大更改滑入了 4.1.0，这使得它们不兼容 (see this issue)。

Npgsql 4.1.1（即将发布）应该再次兼容。同时，您可以尝试更新到 EF Core 3.0，它应该可以很好地与 Npgsql 4.1.0 配合使用。

System.MissingMethodException: 未找到方法：'UInt32 Npgsql.NpgsqlStatement.get_Rows()

System.MissingMethodException: Method not found: 'UInt32 Npgsql.NpgsqlStatement.get_Rows()

npgsql

entity-framework-6

asp.net-core