Fix incorrect block accounting in TID Range Scans heapgettup_advance_block() (or heapgettup() and heapgettup_pagemode() in versions before v16) would incorrectly decrement rs_numblocks when advancing to the next block. Ordinarily this was fine, but if the TID Range scan plan was used by a scrollable cursor and the cursor was fetched backwards enough to result in another block being required, then rs_numblocks may have reached 0 prematurely resulting in the scan ending prematurely.
Reported-by: Jeff Davis <[email protected]> Author: Ewan Young <[email protected]> Discussion: https://postgr.es/m/[email protected] Backpatch-through: 14 Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/cd7d3e129b79ee41c03001550b43b160e10c2f30 Modified Files -------------- src/backend/access/heap/heapam.c | 48 +++++++++++++++++++++++++----- src/test/regress/expected/tidrangescan.out | 26 ++++++++++++++++ src/test/regress/sql/tidrangescan.sql | 12 ++++++++ 3 files changed, 78 insertions(+), 8 deletions(-)
