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更新时间：2024-06-29 GMT+08:00
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WITH AS

WITH AS 在GaussDB(DWS)中用于声明一个或多个可以在主查询中通过名字引用的子查询，相当于临时表。DSC工具支持该关键字，迁移工程中保留。

输入示例

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WITH e AS (
  SELECT city, sum(population) FROM t1 group by city
  ),
  d AS (
  SELECT max(music) as max_music, min(music) as min_music from student
  ),
  s AS (
  SELECT * FROM subject
  )
SELECT * FROM e;

输出示例

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WITH e AS (
  SELECT
    city, sum(population)
  FROM
    t1
  GROUP BY
    city
),
d AS (
  SELECT
    max(music) AS "max_music", min(music) AS "min_music"
  FROM
    student
),
s AS (
  SELECT
    *
  FROM
    subject
)
SELECT
  *
FROM
  e;