Entity Framework Include OrderBy random generates duplicate data

Question

When I retrieve a list of items from a database including some children (via .Include), and order the randomly, EF gives me an unexpected result.. I creates/clones addition

Answer 1

I dont think there is an issue in query generation, but there is definately an issue when EF tries to convert rows into object.

It looks like there is an inherent assumption here that data for the same person in a joined statement will be returned grouped together order by or not.

for example the result of a joined query will always be

P.Id P.Name  A.Id A.StreetLine
1    Person 1 10    --- 
1    Person 1 11
2    Person 2 12
3    Person 3 13
3    Person 3 14 

even if you order by some other column, same person would always appear one after the other.

this assumption is mostly true for any joined query.

But there is a deeper issue here i think. OrderBy is for when you want data in certain order ( as opposite to random), so that assumption does seem reasonable.

i think you should really get data out and then randomize it according to some other means in your code