Node.js · Middle · Question 47 of 75

What is the N+1 query problem?

1Running more than one database server
2A query that returns N+1 rows instead of N
✓Correct answer: Loading a list with one query, then running one more query per item, instead of one or two queries in total

Explanation

For 100 posts it means 101 queries. Fix it with a JOIN, WHERE id IN (...) or batching (e.g. DataLoader in GraphQL).

Further reading

Prisma: Documentation ↗

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