pgsql: Don't test for system columns on join relations

Don't test for system columns on join relations

create_foreignscan_plan needs to know whether any system columns are
requested from a relation (this flag is needed by ForeignNext during
execution). However, for join relations this is a pointless test,
because it's not possible to request system columns from them, so
remove the check.

Author: Etsuro Fujita
Discussion: http://www.postgresql.org/message-id/56AA0FC5.9000207@lab.ntt.co.jp
Reviewed-by: David Rowley, Robert Haas

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/3cb5867b7d346eff4abcb69ca182ba658d5faecc

Modified Files
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src/backend/optimizer/plan/createplan.c | 61 +++++++++++++++++++--------------
1 file changed, 35 insertions(+), 26 deletions(-)