mysql - 如果所有分组的行都是 1，则显示 1，否则显示 0

Question

我有这个查询：

select *, sum(services.amount) as service_amount from invoices
left join projects using(project_id)
left join services using(invoice_id)
where client_id = ?
group by project_id
order by issue_date desc

在表中invoices，我有一列paid是 a tinyintthat is 1or 0。

添加到我的查询中，如果所有分组的列行都相等，如何使返回paid列显示，否则显示该列？1paid10paid

Answer 1

我认为您可以使用 sql 中的min关键字。就像是：

select MIN(paid), sum(services.amount) as service_amount from invoices
left join projects using(project_id)
left join services using(invoice_id)
where client_id = ?
group by project_id
order by issue_date desc

Answer 2

选择最低（付费）也许？如果有 0，则应为 0，否则应为 1。