Deleting list using unitofwork

Question

It is possible to delete list in specific order using unitofwork ? If yes how to do using c#? I have tried but it is always deleting order by primary key.

Tapan Patel · Answer

This is what I would try. Once you do order by , store it in different variable. Meaning , Var newList = oldlist.orderby().toList(); And then, try deleting from newList.

shafique ansari · Answer

Upper level record is attached with lower via foreign key relation.

Tapan Patel · Answer

it would be great if you can explain this dependency becuase if it is self referencing table, then I don't think, you will need to take care of that. Please define internal dependency. The solution, you are looking for doesn't seem to be available through EF - meaning you cannot force EF to do that. I tested out bunch of delete statements directly on server (using SSMS) and it turned out that server decides the deletion order. One way is to have multiple statements and exectue them individually (which is not a good solution). So, if you can explain briefly what sort of internal dependency you are talking about, I can help.

shafique ansari · Answer

Actually I want to make transaction ATOMIC. Do we have any way to force entity framework to delete higher index value first then lower index. Actually we have some internal dependency that is why we want to delete higher index value first .

Tapan Patel · Answer

okay. It seems like EF cannot do that unless you disable the contraints on the table, remove and enable the constraints again. But it is a bad (Really bad) idea. Other than that there is a way (not exactly suitable in production) but you can call commit on each removal of entity objects from UOW (performance hit if number of objects to be removed are multiples). Just out of curiosity, why do you care about order? Is it self referencing table? There could be another way to solve the issue you are trying.

Tapan Patel · Answer

Give me sometime. I will update you on this.

shafique ansari · Answer

I want to delete last record first then second last and so on from the list. unitofwork.Entity.RemoveRange(entityList.OrderbyDescending(x=> x.Id)); unitofwork.Commit(); But it always delete in ascending order of list not descending order. I also also tried List a = new List(); a.Add(new item(){Id =3, name ="C" }); a.Add(new item(){Id =2, name ="B" }); a.Add(new item(){Id =1, name ="A" }); unitofwork.Entity.RemoveRange(a); unitofwork.Commit(); But it tries to delete item with Id 1 first. not with 4. I also tried unitofwork.Entity.Remove(new item(){Id =3, name ="C" }); unitofwork.Entity.Remove(new item(){Id =2, name ="B" }); unitofwork.Entity.Remove(new item(){Id =1, name ="A" }); unitofwork.Commit(); But it tries to delete item with Id 1 first. not with 4.

shafique ansari · Answer

That is not working because entityframwork somehow sort then in ascending order of id once we call unitofWork.commit();

shafique ansari · Answer

I tried creating a fresh list just by adding items in descending order of ids and tried deleting the list but it did not work. Entity framework somehow manage to order them in ascending order of I'd then delete once we call unitofwork.Commit().

shafique ansari · Answer

Any update on this?

shafique ansari · Answer

I have tried unitofwork.Entity.RemoveRange(entityList.OrderbyDescending(x=> x.Id)); unitofwork.Commit(); But it always delete in ascending order of list not descending order.

Tapan Patel · Answer

Please elaborate the context here. You can delete the list in specific order if you know the items in a list or you are aware about index and items. Also, post some code that you have tried. It will help to get to the solution.