SQL为什么预估执行计划与真实执行计划会有差异？http://www.bieryun.com/3149.html 一问题概要对同一个 SQL 语句的 ExplainPlan 里显示的预估执行计划与通过 V$SQL_PLAN 视图获取的 Runtime Plan 真实执行计划，偶尔会发现两边有不一致的情况，为什么呢？为什么预估执行计划会不准确？怎样才能避免这种情况的发生？二问题解答这是.....

文章 2018-04-17 来自：开发者社区

SQL为什么预估执行计划与真实执行计划会有差异？

SQL为什么预估执行计划与真实执行计划会有差异？一问题概要对同一个 SQL 语句的 ExplainPlan 里显示的预估执行计划与通过 V$SQL_PLAN 视图获取的 Runtime Plan 真实执行计划，偶尔会发现两边有不一致的情况，为什么呢？为什么预估执行计划会不准确？怎样才能避免这种情况的发生？二问题解答这是执行计划相关中会被经常问道的问题，也是困扰自己很长时间的问题。希.....

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