+-----+------------+------------+---------------------+
| id | seller_id | prod_id | date |
+-----+------------+----------------------------------+
| 1 | 283 | 4243 | 2016-10-10 23:55:01 |
| 2 | 287 | 4243 | 2016-10-10 02:01:06 |
| 3 | 283 | 4243 | 2016-10-11 23:55:06 |
| 4 | 311 | 4243 | 2016-10-11 23:55:07 |
| 5 | 283 | 4243 | 2016-10-12 23:55:07 |
| 6 | 283 | 4243 | 2016-10-13 23:55:07 |
| 7 | 311 | 4243 | 2016-10-13 23:55:07 |
| 8 | 287 | 4243 | 2016-10-14 23:57:06 |
| 9 | 311 | 4243 | 2016-10-14 23:57:06 |
| 10 | 311 | 4243 | 2016-10-15 23:57:06 |
+-----+------------+------------+---------------------+
从上表中我将如何使用MySQL查询提取以下信息?
+------------+---------+----------------+---------------+
| seller_id | prod_id | streak in days | begin streak |
+-----+------------+--------------------+---------------+
| 283 | 4243 | 4 | 2016-10-10 |
| 287 | 4243 | 1 | 2016-10-10 |
| 311 | 4243 | 1 | 2016-10-11 |
| 311 | 4243 | 3 | 2016-10-13 |
| 287 | 4243 | 1 | 2016-10-14 |
+------------+---------+----------------+---------------|
所以基本上我需要为销售产品的每个卖家(seller_id)确定每个连续日期的块(prod_id)。
我将此示例限制为1个prod_id且仅限几天,但卖家确实销售超过1个产品(prod_id)
答案 0 :(得分:1)
SELECT
seller_id
,prod_id
,COUNT(*) as StreakInDays
,MIN(DateCol) as BeginStreak
FROM
(
SELECT
seller_id
,prod_id
,DATE(DateCol) as DateCol
,(@rn:= if((@seller = seller_id) AND (@prod = prod_id), @rn + 1,
if((@seller:= seller_id) AND (@prod:= prod_id), 1, 1)
)
) as RowNumber
FROM
Transact t
CROSS JOIN (SELECT @seller:=0, @prod:=0, @rn:=0) var
ORDER BY
seller_id
,prod_id
,DATE(DateCol)
) t
GROUP BY
seller_id
,prod_id
,DATE_SUB(DateCol, INTERVAL RowNumber Day)
ORDER BY
prod_id
,DATE_SUB(DateCol, INTERVAL RowNumber Day)
,seller_id
生成由seller_id和prod_id分区的分区行号。然后使用Date - RownNumber作为分组,您可以通过简单的聚合得到答案。
SQL小提示向您展示它适用于多种产品,卖家等。http://sqlfiddle.com/#!9/0a0c44/8/0
请注意,如果同一卖家可能在同一天有一个以上的产品交易,那么您需要在生成之前将Transact替换为DISTINCT seller_id,prod_id,DATE(日期)的派生表行号如下:
SELECT
seller_id
,prod_id
,COUNT(*) as StreakInDays
,MIN(DateCol) as BeginStreak
FROM
(
SELECT
seller_id
,prod_id
,DateCol
,(@rn:= if((@seller = seller_id) AND (@prod = prod_id), @rn + 1,
if((@seller:= seller_id) AND (@prod:= prod_id), 1, 1)
)
) as RowNumber
FROM
(SELECT DISTINCT seller_id, prod_id, DATE(DateCol) as DateCol
FROM
Transact
)t
CROSS JOIN (SELECT @seller:=0, @prod:=0, @rn:=0) var
ORDER BY
seller_id
,prod_id
,DateCol
) t
GROUP BY
seller_id
,prod_id
,DATE_SUB(DateCol, INTERVAL RowNumber Day)
ORDER BY
prod_id
,DATE_SUB(DateCol, INTERVAL RowNumber Day)
,seller_id