• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 1034
  • Last Modified:

SQL query - inclue only work days

Hi experts,

I have to create a query that determines the difference in time between two dates and then calculate the average time difference based on a grouping of another field. There is a trick however - the calculation of the difference in time should exclude Saturdays and Sundays. The query as follows:

SELECT t.name, AVG(DATEDIFF(dd,t.dateone,t.datetwo) AS time
FROM db.dbo.table t
GROUP BY t.name

I have no idea how to do the exclusion of  Saturdays and Sundays in the calculation. Any help would be much appreciated.

Thanks!
0
avdvyver
Asked:
avdvyver
  • 3
  • 2
1 Solution
 
avdvyverAuthor Commented:
My apologies - the query as follows:

SELECT t.name, AVG(DATEDIFF(dd,t.dateone,t.datetwo)) AS time
FROM db.dbo.table t
GROUP BY t.name
0
 
Aneesh RetnakaranDatabase AdministratorCommented:
use this function to get the no of working days b/w 2 dates

CREATE FUNCTION dbo.GetWorkingDays
( @StartDate datetime,
@EndDate datetime )
RETURNS INT
AS
BEGIN
DECLARE @WorkDays int, @FirstPart int
DECLARE @FirstNum int, @TotalDays int
DECLARE @LastNum int, @LastPart int
IF (DATEDIFF(day, @StartDate, @EndDate) < 2)
BEGIN
RETURN ( 0 )
END
SELECT
@TotalDays = DATEDIFF(day, @StartDate, @EndDate) - 1,
@FirstPart = CASE DATENAME(weekday, @StartDate)
WHEN 'Sunday' THEN 6
WHEN 'Monday' THEN 5
WHEN 'Tuesday' THEN 4
WHEN 'Wednesday' THEN 3
WHEN 'Thursday' THEN 2
WHEN 'Friday' THEN 1
WHEN 'Saturday' THEN 0
END,
@FirstNum = CASE DATENAME(weekday, @StartDate)
WHEN 'Sunday' THEN 5
WHEN 'Monday' THEN 4
WHEN 'Tuesday' THEN 3
WHEN 'Wednesday' THEN 2
WHEN 'Thursday' THEN 1
WHEN 'Friday' THEN 0
WHEN 'Saturday' THEN 0
END
IF (@TotalDays < @FirstPart)
BEGIN
SELECT @WorkDays = @TotalDays
END
ELSE
BEGIN
SELECT @WorkDays = (@TotalDays - @FirstPart) / 7
SELECT @LastPart = (@TotalDays - @FirstPart) % 7
SELECT @LastNum = CASE
WHEN (@LastPart <> 0) THEN @LastPart - 1
ELSE 0
END
SELECT @WorkDays = @WorkDays * 5 + @FirstNum + @LastNum
END
RETURN ( @WorkDays )
END
GO

0
 
Patrick MatthewsCommented:
Hi avdvyver,

Aneesh's function will get you there, unless you have to consider "holidays", days that are Mon-Fri but for
one reason or another should not be counted as work days.  Will you need to do this?  If so, then you would
have to maintain a table of such days, and modify Aneesh's function to refer to that table.

Regards,

Patrick
0
Cloud Class® Course: Ruby Fundamentals

This course will introduce you to Ruby, as well as teach you about classes, methods, variables, data structures, loops, enumerable methods, and finishing touches.

 
avdvyverAuthor Commented:
Hi Patrick,

Luckly I don't have to cater for holiday during the working week.
0
 
avdvyverAuthor Commented:
Hi aneeshattingal,

I don't want to sound stuipd ... but I don't understand where the origional query fits into your answer. I'm sure it works, I just don't know where exactly to fit my query in. :)
0
 
Aneesh RetnakaranDatabase AdministratorCommented:
SELECT t.name, AVG(dbo.GetWorkingdays(t.dateone,t.datetwo) AS time
FROM db.dbo.table t
GROUP BY t.name
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Cloud Class® Course: Microsoft Windows 7 Basic

This introductory course to Windows 7 environment will teach you about working with the Windows operating system. You will learn about basic functions including start menu; the desktop; managing files, folders, and libraries.

  • 3
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now