Thread: pgsql: Fix CLUSTER tuplesorts on abbreviated expressions.
Fix CLUSTER tuplesorts on abbreviated expressions. CLUSTER sort won't use the datum1 SortTuple field when clustering against an index whose leading key is an expression. This makes it unsafe to use the abbreviated keys optimization, which was missed by the logic that sets up SortSupport state. Affected tuplesorts output tuples in a completely bogus order as a result (the wrong SortSupport based comparator was used for the leading attribute). This issue is similar to the bug fixed on the master branch by recent commit cc58eecc5d. But it's a far older issue, that dates back to the introduction of the abbreviated keys optimization by commit 4ea51cdfe8. Backpatch to all supported versions. Author: Peter Geoghegan <pg@bowt.ie> Author: Thomas Munro <thomas.munro@gmail.com> Discussion: https://postgr.es/m/CA+hUKG+bA+bmwD36_oDxAoLrCwZjVtST2fqe=b4=qZcmU7u89A@mail.gmail.com Backpatch: 10- Branch ------ REL_11_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/adb2d84fc2d60de45ba936bfbcadb7d56048c30c Modified Files -------------- src/backend/utils/sort/tuplesort.c | 4 +- src/test/regress/expected/cluster.out | 121 ++++++++++++++++++++++++++++++++++ src/test/regress/sql/cluster.sql | 43 ++++++++++++ 3 files changed, 167 insertions(+), 1 deletion(-)