DbUpdateConcurrencyException for entities being fetched from cache on update

[Adnan Kamili]

Summary of the issue

We make all the read queries from a DBContext for which AsNoTracking() is set to true. The EFCoreSecondLevelCache is enabled for this DBContext. Then if a change is required to be made to the entity, we attach it to a different DBContext (which we use for CREATE/UPDATE/DELETE), make changes and save it. The EFCoreSecondLevelCache is enabled for this DBContext too for cache invalidation. But after adding this library interceptor we are frequently getting DbUpdateConcurrencyException exceptions now. The issue resolves if we disable EFCoreSecondLevelCache. Do you have any idea why this could be happening and what we could do to fix this?

Environment

.NET (Core) SDK version: 7
Microsoft.EntityFrameworkCore version: 7
EFCoreSecondLevelCacheInterceptor version: 3.9.4
Database: Postgres
Cache provider: Redis

Output:

Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException: The database operation was expected to affect 1 row(s), but actually affected 0 row(s); data may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=527962 for information on understanding and handling optimistic concurrency exceptions.
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch+<ThrowAggregateUpdateConcurrencyExceptionAsync>d__10.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch+<Consume>d__7.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch+<ExecuteAsync>d__50.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch+<ExecuteAsync>d__50.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor+<ExecuteAsync>d__9.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor+<ExecuteAsync>d__9.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor+<ExecuteAsync>d__9.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager+<SaveChangesAsync>d__106.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager+<SaveChangesAsync>d__110.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlExecutionStrategy+<ExecuteAsync>d__7<TState, TResult>.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.EntityFrameworkCore.DbContext+<SaveChangesAsync>d__64.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.EntityFrameworkCore.DbContext+<SaveChangesAsync>d__64.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at SampleWebApi.Repository.BaseRepository<TContext>+<SaveAsync>d__11.MoveNext() in /home/runner/work/sample-web-api/sample-web-api/Repository/BaseRepository.cs:line 150

[Vahid Nasiri]

The issue resolves if we disable EFCoreSecondLevelCache.

Great! Just don't use it. It will not support misusing EF-Core at all. You are not supposed to use different contexts for your scenarios when concurrency checking is enabled and you even don't know what does it mean and also you don't know EF-Core is not thread-safe.