Good point, but in the case of OP, without condition, it will do a full table sc... | Hacker News

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		acatton on May 31, 2023 \| parent \| context \| favorite \| on: When LIMIT 9 works but LIMIT 10 hangs Good point, but in the case of OP, without condition, it will do a full table scan. Also, any case of "WHERE filter ORDER BY random() LIMIT n" means "I want a tiny sample from a broad filter". So it might not be a full table scan, but it will still assign value to a lot of rows.

cryptonector on May 31, 2023 [–]

> Good point, but in the case of OP, without condition, it will do a full table scan.

And that has nothing to do with the ORDER BY random().

tremon on June 1, 2023 | [–]

Yes it does, because of LIMIT N. An unordered result set will stop after the first N matches.

cryptonector on June 2, 2023 | | [–]

Now that is correct.

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