添加值：mysql的

Question

我有這樣的一個表：使用MySQL

Date      Name  Qty 
2016-09-13 00:00:00  John  2 
2016-09-15 00:00:00  Matt  3 
2016-09-21 00:00:00  Rich  1 
2016-09-23 00:00:00  Matt  1 
2016-10-05 00:00:00  John  1 
2016-10-07 00:00:00  Matt  3 
2016-10-12 00:00:00  Rich  0 
2016-10-23 00:00:00  Matt  2 

我該怎麼辦，檢索除了所有的數量值對應於同月和將該信息放置在視圖上？

Answer 1

什麼你可能想可能是由以下查詢之一：

SELECT YEAR(`Date`) AS yr, MONTH(`Date`) AS mnt, SUM(Qty) AS Qty 
FROM `table1` 
GROUP BY YEAR(`Date`), MONTH(`Date`) 

或

SELECT EXTRACT(YEAR_MONTH FROM `Date`) AS mnt, SUM(Qty) as Qty 
FROM `table1` 
GROUP BY EXTRACT(YEAR_MONTH FROM `Date`) 

這個查詢應該產生這樣的事：

mnt  | qty 
---------+----- 
2016-09 | 7 
2016-10 | 6 

MySQL函數EXTRACT()只能返回一些components of a date。

Answer 2

SELECT sum(Qty) as sum, month(date) as month, year(date) as year FROM table_name GROUP BY month(date), year(date) 

將返回

sum month year  
4  12  2015 
10  12  2016