Question

是否可以获取最小ID的记录并按列分组？（在4.0中）

SELECT period, activity, date
FROM (
    SELECT MIN(id) id
    FROM Booking 
    WHERE place = 'CONFERENCE'          
    AND Date = '05 - Mar'   
    GROUP BY period
) A
INNER JOIN Booking B
USING (id) ORDER BY id

可能等同于4.0版本吗？

Answer 1

我认为以下内容在没有子查询的情况下得到了id的分钟：

select b1.period, b1.activity, b1.date
from booking b1 cross join
     booking b2
group by b1.id, b2.period
having b1.id = min(b2.id)

您可以将where条件应用为：

select b1.period, b1.activity, b1.date
from booking b1 cross join
     booking b2
where b2.place = 'CONFERENCE' and   
      b2.Date = '05 - Mar'   
group by b1.id, b2.period
having b1.id = min(b2.id);

Mysql 4.0获取Min值的数据

1 个答案: