Running a Query with in a foreach loop

[eluser]kgill[/eluser]
I cringe every time I see someone suggest queries in loops, in this case it's fine because I don't think your project list is going to get very big but unless you know it's always going to be a very short list use a join! Using a loop is about as inefficient as it gets, especially when you get into large data sets.

Do the math... suppose you've got 1000 projects that's 1001 hits on the DB for every user that is connecting, if you get 10 users in the space of a second and you just hammered your DB with 10,000 queries in under a second. You can see how that gets bad the larger the data set and the more users connected. If you used a join you'd hit the DB once for each user, the trade off is that you're returning a larger result set and transferring a little more data than running the queries separately.