当前季度的 T-SQL 工作日和当前季度过去的工作日答案

【问题标题】：T-SQL Work days in current quarter and work days passed in current quarter当前季度的 T-SQL 工作日和当前季度过去的工作日
【发布时间】：2018-11-17 00:05:12
【问题描述】：

除了当前季度到目前为止已经过去了多少工作日之外，最好的方法是提取当前季度的工作日数（周一至周五）？这是用于 T-SQL/MS SQL

我有当前的总天数，只需要删除周末...

datediff(dd, dateadd(qq, datediff(qq,0, getdate()),0), dateadd(qq, datediff(qq,0, getdate()) + 1 ,0)) as [Days in Quarter]

【问题讨论】：

您现有的查询告诉我这是 T-SQL，它可能是 MS SQL Server 或 Sybase。创建查询时，始终将数据库指定为标签。 “SQL”是查询标准，不是数据库名称。
日历表。当您说工作日时，您是指周一至周五吗？假期呢？ stackoverflow.com/questions/1201874/…

标签： sql date

【解决方案1】：

一种方法如下：

select
       dates.*

     , (DATEDIFF(dd, startofperiod, endofperiod) + 1)
      -(DATEDIFF(wk, startofperiod, endofperiod) * 2)
      -(CASE WHEN DATENAME(dw, startofperiod) = 'Sunday' THEN 1 ELSE 0 END) 
      -(CASE WHEN DATENAME(dw, endofperiod) = 'Saturday' THEN 1 ELSE 0 END)
      as wkdaysinperiod

     , (DATEDIFF(dd, startofperiod, today) + 1)
      -(DATEDIFF(wk, startofperiod, today) * 2)
      -(CASE WHEN DATENAME(dw, startofperiod) = 'Sunday' THEN 1 ELSE 0 END) 
      -(CASE WHEN DATENAME(dw, today) = 'Saturday' THEN 1 ELSE 0 END)
      as wkdaystodate
from (
    select 
          dateadd(qq, datediff(qq,0, getdate()),0)                     as startofperiod
        , dateadd(dd,-1,dateadd(qq, datediff(qq,0, getdate()) + 1 ,0)) as endofperiod
        , convert(date,getdate()) as today
    ) as Dates
;

上面看到的方法假设使用英语，所以如果不适合模数可以用来删除该依赖关系，如下所示。

SQL Server 中的“基准日期”是 1900-01-01，即星期一，因此自该日期除以 7、0 后的剩余天数为星期一、1、星期二、... 6 星期日。无论服务器 datefirst 设置如何，都是如此。

select
       dates.*, ca.*

     , (DATEDIFF(dd, startofperiod, endofperiod) + 1)
      -(DATEDIFF(wk, startofperiod, endofperiod) * 2)
      -(CASE WHEN periodstartdaynum = 6 THEN 1 ELSE 0 END) /* Sunday */
      -(CASE WHEN periodenddaynum   = 5 THEN 1 ELSE 0 END) /* Saturday */
      as wkdaysinperiod

     , (DATEDIFF(dd, startofperiod, today) + 1)
      -(DATEDIFF(wk, startofperiod, today) * 2)
      -(CASE WHEN periodstartdaynum = 6 THEN 1 ELSE 0 END) /* Sunday */
      -(CASE WHEN todaydaynum       = 5 THEN 1 ELSE 0 END) /* Saturday */
      as wkdaystodate
from (
    select 
          dateadd(qq, datediff(qq,0, getdate()),0)                     as startofperiod
        , dateadd(dd,-1,dateadd(qq, datediff(qq,0, getdate()) + 1 ,0)) as endofperiod
        , convert(date,getdate()) as today
    ) as Dates
cross apply (
    select
          datediff(dd,0,startofperiod) % 7 as periodstartdaynum
        , datediff(dd,0,endofperiod) % 7   as periodenddaynum
        , datediff(dd,0,today) % 7         as todaydaynum
    ) ca
;

【讨论】：