Question

我有三个选择查询，如下所示，提供相应的输出

select DATE_FORMAT(table1.value_date,'%b')as Month,
       DATE_FORMAT(table1.value_date,'%Y') as Year,
       table1.open as Open 
from index_main as table1 
    join ( select min(`value_date`) `value_date` 
           from index_main 
           group by month(`value_date`), year( `value_date`) 
    ) as table2 on table1.`value_date` = table2.`value_date`

输出列 - 月，年，开放

select DATE_FORMAT(table1.value_date,'%b')as Month,
    DATE_FORMAT(table1.value_date,'%Y') as Year,
    table1.close as Open 
from index_main as table1 
    join ( select max(`value_date`) `value_date` 
           from index_main group by month(`value_date`), year( `value_date`) 
    ) as table2 on(table1.`value_date` = table2.`value_date`)

输出列 - 月，年，关闭

select DATE_FORMAT(table1.value_date,'%b')as Month,
    DATE_FORMAT(table1.value_date,'%Y') as Year,
    max(table1.high) as High 
FROM `index_main` as table1 
GROUP BY table1.month,table1.year 
ORDER BY year(table1.value_date) desc, month(table1.value_date) desc

输出列 - 月，年，高，低

我想根据常用列加入这三个选择查询，即月份和时间。年。

我的最终结果应该包含以下列：月，年，开，关，高，低。

Answer 1

试试这个。

首先创建3个视图，每个视图一个（vw1，vw2和vw3）。然后使用如下查询：

SELECT vw1.Month, vw1.Year, Open, Close High FROM vw1 LEFT join vw2 on vw1.Year=vw2.Year and vw1.Month=vw2.Month LEFT JOIN vw3 on vw1.Year=vw3.Year and vw1.Month=vw3.Month

希望这会对你有所帮助。

如何连接三个具有一个公共列的选择查询

1 个答案: