Actually your memory estimate is way off. The where clause eliminates most of the view, and it is possible to generate the view using relatively little working space. (Enough to sort the original dataset by session, then enough working space for processing a single sesion.) In fact assuming a half billion threads with 10 users each, you'd only need 540 GB or so - that's about a 95% saving!

Unfortunately doing anything interesting with the view, such as sorting and grouping it, will require throwing a lot of memory around. (That was where my 12 terabyte back-of-the-envelope estimate came from.)

About query plans, I agree that it is very instructive to see that kind of detail, and I wish more people were aware of it. But at the same time I like not having to think about it unless I really have to think about it.

In reply to Re^5: Catching Cheaters and Saving Memory by tilly
in thread Catching Cheaters and Saving Memory by hgolden

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