API Design · Middle · Question 13 of 75

Why does offset pagination produce duplicates or gaps when items are inserted while paging?

1Databases randomize order each time
✓Correct answer: Positions shift: a new item at the top pushes everything down, so page 2 repeats the last item of page 1
3Offset pagination deletes items

Explanation

Cursor pagination based on a stable sort key (e.g. createdAt, id) doesn't have this problem.

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