[COMMITTERS] pgsql: Fix wrong costing of Sort under Gather Merge.

Fix wrong costing of Sort under Gather Merge.

There's no mechanism for such a sort to become a top-N sort, so we
should pass -1 rather than limit_tuples to cost_sort().

Rushabh Lathia, per a report from Mithun Cy

Discussion: http://postgr.es/m/CAGPqQf1akRcSgC9=6iwx=sEPap9UvPpHJLzg8_N+OuHdb6fL+g@mail.gmail.com

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/dc02c7bca4dccf7de278cdc6b3325a829e75b252

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