每个客户在该特定日期的倒数第五笔交易

Question

我有一个包含信息的表格：

customer_id | Date | Time| Sales 

我们在给定的一天内有多个客户的交易。我如何在任何一天检索每个客户的倒数第五笔交易？

Answer 1

试试这个：

SELECT A.customer_id, A.Date, A.Time, A.Sales 
FROM (SELECT A.customer_id, A.Date, A.Time, A.Sales, 
             IF(@customerId = @customerId:=A.customer_id AND @Date = @Date:=A.Date, @Id:=@ID + 1, @ID:=1) AS RowNum
      FROM tableA A, (SELECT @customerId:=0, @Date:='', @Id:=0) AS B 
      ORDER BY A.customer_id, A.Date, A.Time DESC
     ) AS A
WHERE A.RowNum = 5