子查询中的 Postgresql 列不存在

Question

我需要在 select 语句中包含 subselect，这在 Mysql 中很常见，但在 Postgresql 中不起作用。 我收到错误未定义列：7 错误：“count_receipts”列不存在

select "organizations".*, (
    SELECT count(*) AS count_receipts FROM companies
            JOIN receipts ON receipts.company_id = companies.id
            WHERE companies.organization_id = organizations.id
            GROUP BY companies.organization_id
) as count_receipts 
from "organizations" 
where count_receipts >= 10 
AND count_receipts <= 20  

如果我删除 where 子句，一切正常，并且 count_receipts 列包含在结果中。但在哪里不起作用。

这个sql有什么问题？

Answer 1

不要将子查询用作列，而是在联接中使用它：

SELECT o.*, count_receipts
FROM organizations o
JOIN (
  SELECT c.organization_id, count(*) AS count_receipts 
  FROM companies c
  JOIN receipts r ON r.company_id = c.id
  GROUP BY c.organization_id
) AS s on s.organization_id = o.id
WHERE count_receipts >= 10 
AND count_receipts <= 20;