Fix handling of opclauses in extended statistics
We expect opclauses to have exactly one Var and one Const, but the code
was checking the Const by calling is_pseudo_constant_clause() which is
incorrect - we need a proper constant.
Fixed by using plain IsA(x,Const) to check type of the node. We need to
do these checks in two places, so move it into a separate function that
can be called in both places.
Reported by Andreas Seltenreich, based on crash reported by sqlsmith.
Backpatch to v12, where this code was introduced.
Discussion: https://postgr.es/m/8736jdhbhc.fsf%40ansel.ydns.eu
Backpatch-to: 12
Branch
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REL_12_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/42276976a1437c88fb6176fc1a876fd79a139eb0
Modified Files
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src/backend/statistics/extended_stats.c | 76 ++++++++++++++++++++----
src/backend/statistics/mcv.c | 27 +++------
src/include/statistics/extended_stats_internal.h | 2 +
3 files changed, 73 insertions(+), 32 deletions(-)
