SQL Server transpose a query result - sql-server

Question

I have a table with the following data:
ItemId PendingTime
1 2016-11-23 15:57:56.000
2 2016-07-09 17:33:09.000
3 2015-11-27 18:34:03.000
and so on..
I would like to know sum of items pending since last 30 mins, last 1 hr, last 1 week, last 1 month and over an year. I came up with the following query:
SELECT
SUM(CASE
WHEN datediff(MINUTE, PENDING_TIME,GETDATE()) <= 30
THEN 1 ELSE 0
END) AS '30 Min',
Sum(case when (datediff(MINUTE,PENDING_TIME, GETDATE())) > 30 AND (datediff(MINUTE,PENDING_TIME, GETDATE())) <= 60 then 1 Else 0 End) as 'Over 30 Min',
Sum(case when (datediff(MINUTE,PENDING_TIME, GETDATE())) > 60 AND (datediff(HOUR,PENDING_TIME, GETDATE())) <= 24 then 1 Else 0 End) as 'Over 1 Hr',
Sum(case when (datediff(DAY,PENDING_TIME, GETDATE())) > 1 AND (datediff(DAY,PENDING_TIME, GETDATE())) < 30 then 1 Else 0 End) as '1 month',
Sum(case when datediff(DAY,PENDING_TIME, GETDATE()) >= 30 then 1 Else 0 End) as 'More than month'
from ItemsTable where datepart(yyyy,PENDING_TIME) = DATEPART(yyyy,GETDATE())
This returns data as:
30 Min Over 30 Min Over 1 Hr 1 month More than month
----------- ----------- ----------- ----------- ---------------
100 350 NULL NULL NULL
I would like the results in 2 column format as:
30 Min ------ 45
Over 30 ------ 100
Over 1 hr ------ null
Over 1 month ------ null
I am aware of the pivot function, however the columns I have selected aren't really in the table I am selecting from, rather they are created as result of aggregate function.
How do I get this in 2 column and multiple rows format.
Thanks for reading through.

Answer 1

You can create a derived column which classifies the waits into different types, then group by that column:
With waitCodes As (
Select Case
When DateDiff(Minute, PENDING_TIME, GetDate()) <= 30 Then '30 Min'
When DateDiff(Minute, PENDING_TIME, GetDate()) <= 60 Then 'Over 30'
When DateDiff(Minute, PENDING_TIME, GetDate()) <= 1440 Then 'Over 1 hr'
When DateDiff(Minute, PENDING_TIME, GetDate()) <= 43200 Then '1 month'
Else 'More than a month' End As [WaitTime]
From ItemsTable
Where DatePart(yyyy, PENDING_TIME) = DatePart(yyyy,GetDate()))
Select [WaitTime], Count(*) As n
From waitCodes
Group By [WaitTime];
In addition, I strongly recommend you change the Where clause in your query so that it doesn't apply a function to the PENDING_TIME column. There are multiple benefits of this.
...
Where PENDING_TIME >= Convert(date, Convert(char(4), DatePart(yyyy, GetDate()))+'-01-01 00:00:00.000', 121)
And PENDING_TIME < Convert(date, Convert(char(4), DatePart(yyyy, GetDate())+1)+'-01-01 00:00:00.000', 121)
....

Answer 2

you can use cross apply statement per orignal sql like this
SELECT c.* FROM
(
SELECT
SUM(CASE
WHEN datediff(MINUTE, PENDING_TIME,GETDATE()) <= 30
THEN 1 ELSE 0
END) AS '30 Min',
Sum(case when (datediff(MINUTE,PENDING_TIME, GETDATE())) > 30 AND (datediff(MINUTE,PENDING_TIME, GETDATE())) <= 60 then 1 Else 0 End) as 'Over 30 Min',
Sum(case when (datediff(MINUTE,PENDING_TIME, GETDATE())) > 60 AND (datediff(HOUR,PENDING_TIME, GETDATE())) <= 24 then 1 Else 0 End) as 'Over 1 Hr',
Sum(case when (datediff(DAY,PENDING_TIME, GETDATE())) > 1 AND (datediff(DAY,PENDING_TIME, GETDATE())) < 30 then 1 Else 0 End) as '1 month',
Sum(case when datediff(DAY,PENDING_TIME, GETDATE()) >= 30 then 1 Else 0 End) as 'More than month'
from ItemsTable where datepart(yyyy,PENDING_TIME) = DATEPART(yyyy,GETDATE())
)
CROSS APPLY(VALUES('30 MIN',a),('Over 30',b),('Over 1 hr',c),('Over 1 month',d),('More than month',e)) c(title,[value])
result:
title value
--------------- -----------
30 MIN 100
Over 30 350
Over 1 hr NULL
Over 1 month NULL
More than month NULL