Hacker News Reader

Think of it the other way around, their engineers didn't optimize any queries and they don't have a dba watching for table scans or nested loop joins. To the amateur crowd it looks like "wow optimization" but if you've been developing seriously for your career this should look like "you have a lot to learn".

View on HN

Yes, but StackOverflow does have a DBA, and very good one at that: http://www.brentozar.com/

I guess he doesn't deal w/ this level of optimization, or it never hit his radar.

Sometimes table scans happen even when you think you know what you're doing. If someone adds a column and doesn't think anyone will be filtered on that column then it can easily happen. I usually ask people:

- how big is this table getting? - how are you querying on it?

That usually fixes most problems before they happen. Not sure it's my job to specify a join type though. A nested loop join isn't a bad thing or even a sign of a bad thing happening necessarily.

Reply on news.ycombinator.com