Question

所以我有一个跟踪日历上事件的MySQL数据库。我有一个名为日历的表，其中包含与我有关的所有日期。在我的工作中，我们有合同具有一定的价值;为简化起见，我们将仅使用1和2.这些合同具有开始日期和结束日期。我想获取整个日历的所有合约，并将每天的合约价值加起来。

到目前为止，我有：

SELECT calendar.datefield AS DATE, contract.time_slots AS Slots_taken
FROM contract
RIGHT JOIN calendar ON calendar.datefield
BETWEEN contract.start_time
AND contract.end_time
LIMIT 600 , 30

这几乎给了我想要的东西。此查询生成如下表：

    DATE    |  Slots_taken
------------|--------------
2013-08-29  |     1
2013-08-30  |     1
2013-08-31  |     1
2013-09-01  |     1
2013-09-01  |     2
2013-09-02  |     1
2013-09-02  |     2
2013-09-03  |     1
2013-09-03  |     2

但是我在这里重复约会。我希望每个日期只有一行，其中包含该日期值的总和。所以它应该是：

    DATE    |  Slots_taken
------------|--------------
2013-08-29  |     1
2013-08-30  |     1
2013-08-31  |     1
2013-09-01  |     3
2013-09-02  |     3
2013-09-03  |     3

Answer 1

SELECT calendar.datefield AS DATE, SUM(contract.time_slots) AS Slots_taken
FROM contract
RIGHT JOIN calendar ON calendar.datefield
BETWEEN contract.start_time
AND contract.end_time
GROUP BY DATE
LIMIT 600 , 30

Answer 2

如果它是普通的tSQL，我建议使用SUM（）和GROUP BY：

SELECT calendar.datefield AS DATE, sum(contract.time_slots) AS Slots_taken
FROM contract
RIGHT JOIN calendar ON calendar.datefield
BETWEEN contract.start_time
AND contract.end_time
LIMIT 600 , 30
GROUP BY calendar.datefield

禁止LIMIT，因为它不是'普通'tSQL

希望它有所帮助

修改

怎么样：

 SELECT DATE, SUM(Slots_taken) AS Slots_taken
 FROM (
   SELECT calendar.datefield AS DATE, contract.time_slots AS Slots_taken
   FROM contract
   RIGHT JOIN calendar ON calendar.datefield
   BETWEEN contract.start_time
   AND contract.end_time
   LIMIT 600 , 30) A
 GROUP BY calendar.datefield

同样，它更像是'普通'tSQL，这是一个查询的笑话：）

Answer 3

SELECT calendar.datefield date
     , SUM(contract.time_slots) slots_taken
  FROM calendar
  LEFT 
  JOIN calendar 
    ON calendar.datefield BETWEEN contract.start_time AND contract.end_time
 GROUP
    BY date
 LIMIT 600 , 30;

如何在分页后对行进行求和？

3 个答案: