Question

I was wondering if it which is faster when trying to, for example, check how many posts are in a particular thread on a forum. Should I…

(a) Go through each post in the database with the particular thread ID, and count how many rows

or

(b) Add one to a separate column in the threads database every time a thread is made, and then query that single row

Thanks.

Answer 1

What’s wrong with having an index for the thread ID? Wouldn’t a simple COUNT expression grouped by the thread ID field suffice?

With any caching at all, this would be plenty fast from what I can tell.

--This will provide counts for all threads SELECT COUNT(threadID) FROM Posts GROUP BY threadID;   --This will provide count for one thread SELECT COUNT(threadID) FROM Posts WHERE threadID=123 GROUP BY threadID;