pgsql: For partitionwise join, match on partcollation,not parttypcoll.

For partitionwise join, match on partcollation, not parttypcoll.

The previous code considered two tables to have the partition scheme
if the underlying columns had the same collation, but what we
actually need to compare is not the collations associated with the
column but the collation used for partitioning.  Fix that.

Robert Haas and Amit Langote

Discussion: http://postgr.es/m/0f95f924-0efa-4cf5-eb5f-9a3d1bc3c33d@lab.ntt.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2af28e603319224e87fd35ab62f36ef6de45eaac

Modified Files
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src/backend/optimizer/util/plancat.c | 6 +++---
src/include/nodes/relation.h         | 2 +-
2 files changed, 4 insertions(+), 4 deletions(-)