如何重用使用“WITH”运算符声明的 Postgres 变量

问题描述

我需要从两个表中删除记录，但我不能一致地执行它，因为从第一个表删除后，第二个表将没有数据要删除。 我试过以下：

WITH person_ids AS(select person_id from application_person 
                              where application_id in (select disTINCT duplicate.id 
                                    from application duplicate inner join application application
                                    on duplicate.document_id = application.document_id
                                    where duplicate.modify_date < application.modify_date)),delete from application_person where application_person.person_id in (select person_id from person_ids);

delete from person where id in (select person_id from person_ids);

对于 person_ids 的第二次调用，我有 Query Failed: ERROR: relation "person_ids" does not exist

我做错了什么？ 谢谢。

解决方法

我做错了什么？

您有两个单独的声明。 person_ids 仅在第一个范围内，一直持续到分号。

你会想要使用

WITH duplicate_applications AS (
  select DISTINCT duplicate.id 
  from application duplicate
  inner join application application using (document_id)
  where duplicate.modify_date < application.modify_date)
),deleted_persons AS (
  delete from application_person
  where application_id in (select application_id from duplicate_applications)
  returning person_id
)
delete from person
where id in (select person_id from deleted_persons);