Question

考虑一个名为'Calls'的表，除其他外，包含以下列：

  CalledNumber | CallBegin
-----------------------------------
004401151234567|10/08/2013 09:06:53
004303111238493|15/09/2013 14:56:29

依旧......

如何选择在日期范围内平均保持最高行数的小时？目标是在一年内找到每个季度的“忙时”。 SQL真的不是我的强项，我正在考虑有时操纵高达9.6万行，但执行时间不是关键问题。

Answer 1

DATEPART正是您所寻找的：

SELECT
    DATEPART(hour, CallBegin), COUNT(*) as NumberOfCalls
FROM
    Test
WHERE
    CallBegin BETWEEN '2013-01-01' AND '2013-12-31'
GROUP BY
    DATEPART(hour, CallBegin)
ORDER BY
    NumberOfCalls DESC

工作DEMO

Answer 2

您可以使用DATEPART()和CONVERT()，我假设CallBegin未存储为日期时间：

SELECT  YEAR(CONVERT(DATETIME,CallBegin,103))'Year'
      , DATEPART(quarter,CONVERT(DATETIME,CallBegin,103))'Quarter'
      , DATEPART(hour,CONVERT(DATETIME,CallBegin,103))'Hour'
      , COUNT(*)
FROM Calls
GROUP BY YEAR(CONVERT(DATETIME,CallBegin,103))
       , DATEPART(quarter,CONVERT(DATETIME,CallBegin,103))
       , DATEPART(hour,CONVERT(DATETIME,CallBegin,103))

如果你想跨越几年，只需消除年份部分：

SELECT  DATEPART(quarter,CONVERT(DATETIME,CallBegin,103))'Quarter'
      , DATEPART(hour,CONVERT(DATETIME,CallBegin,103))'Hour'
      , COUNT(*)
FROM Calls
GROUP BY DATEPART(quarter,CONVERT(DATETIME,CallBegin,103))
       , DATEPART(hour,CONVERT(DATETIME,CallBegin,103))

Answer 3

使用DATEPART。即，

SELECT  DATEPART(hh, CallBegin) ,
    COUNT(1) as callCount
FROM Calls
GROUP BY DATEPART(hh, CallBegin)
ORDER BY callCount DESC

Answer 4

而不是datePart，请尝试使用DateAdd()和DateDiff()

  Select top 1 DateAdd(hour, DateDiff(hour, 0, CallBegin), 0)
  From Calls
  Group By DateAdd(hour, DateDiff(hour, 0, CallBegin), 0) 
  Order By Count(*) Desc

这样做会更好，因为它纯粹是算术运算，即没有解析日期和/或日期时间的文本表示。

添加计数以查看在该小时内发生的次数

  Select top 1 DateAdd(hour, DateDiff(hour, 0, CallBegin), 0), Count(*)
  From Calls
  Group By DateAdd(hour, DateDiff(hour, 0, CallBegin), 0) 
  Order By Count(*) Desc

获得最高行数的小时

4 个答案: