Thanks Tender -- you're right, this is the same issue as #19501 (Man Zeng, 2026-05-29), which I missed before posting. Apologies for the duplicate; let's consolidate on that thread.
On Wed, Jun 17, 2026 at 5:56 PM Tender Wang <[email protected]> wrote: > > Ewan Young <[email protected]> 于2026年6月17日周三 16:40写道： > > > > Hi, > > > > A GiST index on a float4/float8 column (via btree_gist) can silently > > omit rows containing NaN, returning different results from a sequential > > scan: > > > > CREATE EXTENSION btree_gist; > > CREATE TABLE t (a float8); > > INSERT INTO t SELECT 1 FROM generate_series(1, 1000); > > INSERT INTO t SELECT 'NaN' FROM generate_series(1, 1000); > > CREATE INDEX ON t USING gist (a); > > > > SET enable_seqscan = on; > > SELECT count(*) FROM t WHERE a = 'NaN'; -- 1000 > > SET enable_seqscan = off; > > SELECT count(*) FROM t WHERE a = 'NaN'; -- 0 (wrong) > > > > It seems the issue you reported is the same as [1]. > Please double-check. > > [1] > https://www.postgresql.org/message-id/19501-3bff3bbc97f1e7c9%40postgresql.org > > > -- > Thanks, > Tender Wang
