849110dd3e
Presently, each iteration of the loop in sift_down() will perform 3 comparisons if both children are larger than the parent node (2 for comparing each child to the parent node, and a third to compare the children to each other). By first comparing the children to each other and then comparing the larger child to the parent node, we can accomplish the same thing with just 2 comparisons (while also not affecting the number of comparisons in any other case). Author: ChangAo Chen Reviewed-by: Robert Haas Discussion: https://postgr.es/m/tencent_0142D8DA90940B9930BCC08348BBD6D0BB07%40qq.com
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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