This patch causes one postgres_fdw test case to revert to the plan it used before aa86129e1, i.e., using a remote sort in preference to local sort. That decision is actually a coin-flip because cost_sort() will give the same answer on both sides, so that the plan choice comes down to little more than roundoff error. In consequence, the test output can change as a result of even minor changes in nearby costs, as we saw in aa86129e1 (compare also b690e5fac and 4b14e1871). b690e5fac's solution to stabilizing the adjacent test case was to disable sorting locally, and here we extend that to the currently- problematic case. Without this, the following patch would cause this plan choice to change back in this same way, for even less apparent reason. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Chao Li <li.evan.chao@gmail.com> Discussion: https://postgr.es/m/2551253.1766952956@sss.pgh.pa.us
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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