mirror of
https://github.com/postgres/postgres.git
synced 2025-05-20 05:13:53 +03:00
87027cb55b
This is extracted from a larger patch to improve the UNION planner. While working on that, I found myself having to check what the 'rows' parameter is for. It's not obvious that passing a negative number is the way to have the rows estimate calculated and to find that out you need to read code in create_append_path() and in cost_append(). Discussion: https://postgr.es/m/CAApHDvpb_63XQodmxKUF8vb9M7CxyUyT4sWvEgqeQU-GB7QFoQ@mail.gmail.com