Check all four box corners in SP-GiST quad tree <@ search When the centroid lies outside the query box, spg_quad_inner_consistent() keeps only the quadrants that contain a corner of the box. It meant to test all four corners, but the last step set x back to low.x instead of y to low.y, so it tested (low.x, high.y) twice and never (high.x, low.y).
With exact comparisons the missing corner would not matter: a box that does not contain the centroid lies on one side of it on at least one axis, so (high.x, low.y) shares a quadrant with another corner, but getQuadrant() compares with FPeq(), which tiebreaks to the lowest numbered quadrant. When a box edge lies within EPSILON of the centroid, the corner on that edge counts as being on the centroid's line, and (high.x, low.y) may be the only corner in its quadrant. That quadrant was then skipped. Fix the missing corner test. Discussion: https://postgr.es/m/CANWCAZZZpkwrX0kC4Jo6KM27J6dyBdCDir-PbjEYAS06r%3D4-ag%40mail.gmail.com Backpatch-through: 14 Branch ------ REL_16_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/9cba87fe947fc3e713bb4ba3be25e34fdb64266d Modified Files -------------- src/backend/access/spgist/spgquadtreeproc.c | 2 +- src/test/regress/expected/spgist.out | 9 +++++++++ src/test/regress/sql/spgist.sql | 5 +++++ 3 files changed, 15 insertions(+), 1 deletion(-)
