C#•2y ago

❔ Ef tracking issue

I'm getting a "instance of entity cannot be tracked because another instance with the key value {productNo:10492} is already being tracked}" I have asNoTracking on my dB call, I've tried to detach all entities but there are none I've tried to remove as many relationships with the productNo as I can and nothing works

9 Replies

Angius•2y ago

IME this error happens when some async calls are not awaited, or when you have an async void method somewhere That's usually the culprit

nauvran•2y ago

The main dB call is awaited and the new smaller call I've made is also awaited The only async void method isn't being used and I just removed the async part and tried again So sadly not that easy a fix :/ Var test2 = await _appDbContext.Products.AsNoTracking.Where(x => x.LocationNo = containerToMoveFrom.Trolley.AssetType).ToListAsync() Then I change some stuff like the locationNo to move the items This is done via a foreach where I modify the list of objects from above linq Then I simply use _appDbContext.UpdateRange(products)

Angius•2y ago

Uh It's non-tracking And you use the result to update the records? Preventing that is explicitly the purpose of non-tracking queries

nauvran•2y ago

Yes I only add non tracking after getting the error as I thought that would fix it

Angius•2y ago

Instead of UpdateRange, after you're done updating the items, just call SaveChangesAsync() on the context

var things = await _ctx.Things.ToListAsync();

foreach (var t in things)
{
    t.Name = $"New Name {t.Name}";
}

await _ctx.SaveChangesAsync();

var things = await _ctx.Things.ToListAsync();

foreach (var t in things)
{
    t.Name = $"New Name {t.Name}";
}

await _ctx.SaveChangesAsync();

nauvran•2y ago

Worth a shot Give me a moment Huh that worked How come update range broke it completely? Thanks a lot ZZZ I've spent all day stuck on this issue trying different things

Angius•2y ago

Update() and UpdateRange() also attach detached entities, or even completely unrelated ones, so something might've gone wrong there, dunno I never use them tbh And, seeing how it was the culprit, I'd say don't use them either lol

nauvran•2y ago

I only use them because it's what I've been taught Oh well, but really thanks a lot

Accord•2y ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

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❔ Ef tracking issue