[aayjaychan]

navigation properties are not loaded automatically, because they can be expensive. you need to use `.Include(foo => foo.Bars)` to tell EF to retrieve them.

EF tries to be smart and will fix up the property in memory if the referenced entities are returned in separate queries. but if those queries don't return all records in `Foo.Bar`, `Foo.Bar` will only be partially populated.

this can be confusing and is one of the reasons i almost never use navigation properties when working with EF.

[LandR]

We have those, and when I say inconsistent I mean inconsistent on the same query / exact same line of code on the same database.

e.g. stick a breakpoint, step over, see in the debugger that it was not populating everything it should. Then run it again, do the same and see different results. Exact same code, exact same db, different results.

5000 results back from the db, anything between 5000 and a handful were only fully correctly populated.

[viraptor]

If that happens with the correct `.Include()`, you really should raise an issue with EF, trying to reproduce it. If it's not a random mistake in your code, that's a really big deal.

[thaumasiotes]

Like your parent said, the same line of code will or won't populate the navigation property depending on whether EF is already tracking the entity that belongs there (generally because some other earlier query loaded it). You get different behavior depending on the state of the system; you can't look at "one line of code" in isolation unless that line of code includes every necessary step to protect itself against context sensitivity.