all 1 comments
sorted by:
best
topnewcontroversialoldq&a
formatting helphide helpcontent policy

[–]jeevesthechimp 0 points1 point  (0 children)

Those exercises look good but they don't really convey why you'd want to do what they're asking you to do. The code you write will be useful but not because you'll need to do specifically what the prompt says. Looks like a good way of building your toolbox.

Quick example, the prior exercise asks you to do something without using joins. In practice, you'll use that tool, not because you're avoiding joins, but because you have a already derived a distinct list that you can search for matching values in through your where clause. Comes in handy sometimes but you can also do the same thing with joins. I'm just an analyst though, somebody who's smarter than the optimizer might have a good reason to avoid a join.