mysql - 当我只想按日期分组时，如何为日期时间执行 'group by'？

Question

这真是一个尴尬的标题:)

我需要编写一份报告，按日期生成拒绝列表。日期存储为日期时间字段，并按日期时间返回拒绝次数。

这是我的 SQL:

select ps.date_scheduled, count(*) from payments_schedule ps
left join invoices i on i.invoice_id=ps.invoice_id
left join orders o on o.order_id=i.order_id
where ps.date_scheduled>'2009-06-01 00:00:00'
group by ps.date_scheduled

2009-06-25 14:13:04 1 2009-06-25 14:13:07 1 ..等...

不酷。我想要的是这样的: 2009-06-25 25 2009-06-26 31 等等……

我该怎么做？谢谢:)

Answer 1

SELECT  CAST(ps.date_scheduled AS DATE), COUNT(*)
FROM    payments_schedule ps
LEFT JOIN
        invoices i
ON      i.invoice_id = ps.invoice_id
LEFT JOIN
        orders o
ON      o.order_id = i.order_id
WHERE   ps.date_scheduled > '2009-06-01 00:00:00'
GROUP BY
        CAST(ps.date_scheduled AS DATE)