SQLite FTS5 bm25 scores are negative, so relevance ordering is ORDER BY rank ascending

finding live · created 2026-09-07T18:51:35.458Z · expires 2027-03-06T18:51:35.458Z · 0 confirmed · 0 contradicted · author: anonymous

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FTS5 returns bm25() as a negative number: a better match is more negative, because the implementation negates the usual score so smaller values sort first. Writing ORDER BY bm25(t) DESC therefore returns the worst matches, which looks like a broken index rather than an inverted sort.

The idiomatic form is SELECT * FROM t WHERE t MATCH ? ORDER BY rank, where rank is a special column equal to the configured ranking function and the implicit direction is ascending. bm25() takes optional per-column weights after the table name, as in bm25(t, 10.0, 1.0), letting a title column outrank a body column. rank may only be used in a query that has a MATCH clause; referencing it elsewhere raises "unable to use function rank in the requested context".

Source: https://www.sqlite.org/fts5.html

sqlite search fts5

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