從tbl'value1'中減去'上一個值'

Question

SELECT  totalAmount 
FROM  tbl 
BETWEEN  'date1' AND 'date2' 

GROUP BY DATE(date created) 
ORDER BY DATE(date created) 

這給了我表中每天的總金額。但我要的是相比前項增量值（不一定是前一天）

表可能是這樣的：

totalAmount | date created 
--------------------------------- 
1000   | 1st Jan 
1001   | 2nd Jan 
1003   | 3rd Jan 
1008   | 15th Jan 

那麼，我的查詢將返回： 1000,1001， 1003,1008。

什麼其實我想要的是：（相比之前的條目數 - 但不是內BETWEEN日期範圍，以便開始我的incriments） ，1,2,5-

Answer 1

這有啥可做到這一點：

SELECT IFNULL((t1.totalamount - t2.totalamount),0) as diff, t1.date_created 
FROM view t1 LEFT OUTER JOIN view t2 
ON t2.date = (SELECT MAX(date) FROM view WHERE date < t1.date) 
WHERE t1.date_created BETWEEN 'date1' AND 'date2' 
ORDER BY date_created 

其中，「意見」是這樣的查詢：

SELECT date_created, SUM(totalamount) FROM tbl GROUP BY date_created 

Answer 2

試試這個：

SELECT  totalAmount 
FROM  tbl 
BETWEEN  'date1' AND 'date2' 

GROUP BY DATE(date created) 
ORDER BY totalAmount DESC, DATE(date created) 

Answer 3

您需要加入兩個相同的排名子查詢。我沒有一個MySQL數據庫來測試這對但形式將類似於：

select t1.TotalAmount, t1.DateCreated, 
    t1.TotalAmount - t2.TotalAmount as 'Delta' 
from 
(select rownum, TotalAmount 
from tbl 
order by DateCreated) t1 
left outer join 
(select rownum, TotalAmount 
from tbl 
order by DateCreated) t2 
on t1.rownum = t2.rownum + 1 
order by t1.rownum