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I think we killed it :)

Back alive atm ( disabled RSS sync :p )

If anyone knows how to performantly sort on non deterministic computed columns ( eg. the ranking algorithm for votes of posts + comments) in MS SQL server -> https://dba.stackexchange.com/questions/203331/slow-calculat... i'd be very happy :p, it's killing my "trending topic" performance...

Edit: added non deterministic

You don't do the calculation on the fly, you do it at data mutation time (if the column should be the same for every client) or in a separate "thread" (eg, a script). Basically, you pre calculate the column and simply add it to your table, indexed.

It's non deterministic because it has a time variation ( newer posts get ranked higher).

Even then?

Don't modify the scores of old posts, start newer ones with a higher score.

Check out how reddit does it: https://medium.com/hacking-and-gonzo/how-reddit-ranking-algo...

The concept is that the time-based part of the score is immutable, fixed at post creation time.

That way you only have to recalculate when a score-modifying event occurs, not every time the page is refreshed.

Good advice, thx!

you've got to double tap to make sure, rules of surviving rss is undead land.

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