3 ms·

You see it in direct code too, from new or naive coders (the good old "it was fast enough on my test data…") or when proof-of-concept code "accidentally" escape

You see it in direct code too, from new or naive coders (the good old "it was fast enough on my test data…") or when proof-of-concept code "accidentally" escapes into production. Even within the database you'll sometimes find examples: stored procedures looping over a cursor and running queries or other statements in each iteration. This doesn't have the same latency implications as N+1 requests over a network, but still does add significant time per step compared to a set based equivalent. If you think about it, the database will sometimes do this itself when your database is not optimally structured & indexed for your queries (in SQL Server, look at "number of executions" in query plans).

nicoburns 4y ago
> You see it in direct code too, from new or naive coders Many moons ago in one of my first coding projects I not only used a separate query for each record, but a separate database connection too. In addition to this, I didn't use a loop to generate these queries, I copy and pasted the connection setup and query code for each record, leading to a 22k code file just for this single web page. There were probably on the order of 1000 records (they represented premier league football players), and amazingly this code was fast enough (took a couple of seconds to load - which wasn't so unusual back in 2007) and worked well enough that it actually had ~100 real users (not bad a 14 year old's side project).