Question

I was checking the docs of postgresql for Recursive queries where I got an example.

WITH RECURSIVE t(n) AS (
    VALUES (1)
  UNION ALL
    SELECT n+1 FROM t WHERE n < 100
)
SELECT sum(n) FROM t

以上说明与100份选举考试委员会声明相同。参考:

<代码> 风险查询通常用于处理等级或树木结构化数据。

If I want to sort the hierarchical structure based on some criteria will it be advisable to recursive query. eg. SQL Query: Fetch ordered rows from a table - II and the accepted answer. Should the data be retrieved from the DB and then sorted in memory. Or RECURSIVE query will be more effcient !!

Answer 1

答案取决于您的图表设计、硬件/OS、配置和装满的数据数量。以解释和解释分析方法,并在几个典型查询中找到最快的方法。

即使我有足够的信息来猜测你的图象和上图数据,对我来说,任何答案都可能不利于奥约。

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