Software Engineering · Performance
A data-fetching pattern where you make one query to get a list of N items, then run one additional query per item to fetch related data — totaling N+1 round-trips instead of one.
Example: Fetching 100 posts then running a separate query for each post's author.
In practice: A common ORM trap — the fix is eager loading the relationship in one query upfront. N+1 is usually the first thing to look for when a page that 'shouldn't be slow' turns out to be.