pgsql: Save PathTargets for distinct/ordered relations inroot->upper_t

Save PathTargets for distinct/ordered relations in root->upper_targets[].

For the convenience of extensions, we previously only saved PathTargets
for grouped, window, and final relations in root->upper_targets[] in
grouping_planner().  To improve the convenience, save PathTargets for
distinct and ordered relations as well.

Author: Antonin Houska, with an additional change by me
Discussion: https://postgr.es/m/10994.1549559088@localhost

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3fdc374b5d24b08119a91555ca2fae427af0b085

Modified Files
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src/backend/optimizer/plan/planner.c | 2 ++
1 file changed, 2 insertions(+)