Re: flink sql支持Common Table Expression (CTE)吗？

2021-05-23 文章 Jingsong Li 
支持。

如果只是在单个sql中复用expression，和temporary view基本一样，区别不大。

在某些优化路径上不同，一般没有实质影响。

Best,
Jingsong

On Fri, May 21, 2021 at 11:32 PM casel.chen  wrote:

> flink sql支持Common Table Expression (CTE)吗？是不是可以通过 create temporary view
> xxx 来实现？CTE和temporary view的区别是什么？
> 例如
>
>
> with toronto_ppl as (
> SELECT DISTINCT name
> FROM population
> WHERE country = "Canada"
>   AND city = "Toronto"
> )
>, avg_female_salary as (
> SELECT AVG(salary) as avgSalary
> FROM salaries
> WHERE gender = "Female"
> )
> SELECT name
>  , salary
> FROM People
> WHERE name in (SELECT DISTINCT FROM toronto_ppl)
>   AND salary >= (SELECT avgSalary FROM avg_female_salary)



-- 
Best, Jingsong Lee

flink sql支持Common Table Expression (CTE)吗？

2021-05-21 文章 casel.chen 
flink sql支持Common Table Expression (CTE)吗？是不是可以通过 create temporary view xxx 
来实现？CTE和temporary view的区别是什么？
例如


with toronto_ppl as (
SELECT DISTINCT name
FROM population
WHERE country = "Canada"
  AND city = "Toronto"
)
   , avg_female_salary as (
SELECT AVG(salary) as avgSalary
FROM salaries
WHERE gender = "Female"
)
SELECT name
 , salary
FROM People
WHERE name in (SELECT DISTINCT FROM toronto_ppl)
  AND salary >= (SELECT avgSalary FROM avg_female_salary)