SQL Query for Null, Zero, and Constant Data - sql

Question

I have a query and I just want to modify it (This query is not written by me).
SELECT CAST(DATEPART(yyyy, UTCTimeStamp) AS VARCHAR(4)) + '-'
+ CAST(DATEPART(mm, UTCTimeStamp) AS VARCHAR(2)) + '-'
+ CAST(DATEPART(dd, UTCTimeStamp) AS VARCHAR(2)) + ' '
+ CAST(DATEPART(hh, UTCTimeStamp) AS VARCHAR(2)) + ':00:000 - '
+ CAST(DATEPART(yyyy, UTCTimeStamp) AS VARCHAR(4)) + '-'
+ CAST(DATEPART(mm, UTCTimeStamp) AS VARCHAR(2)) + '-'
+ CAST(DATEPART(dd, UTCTimeStamp) AS VARCHAR(2)) + ' '
+ CAST(DATEPART(hh, UTCTimeStamp) AS VARCHAR(2)) + ':45:000' AS HourTime ,
SUM(CASE WHEN ElapsedValue IS NULL THEN 1
ELSE 0
END) AS NoData ,
SUM(CASE WHEN ElapsedValue = 0 THEN 1
ELSE 0
END) AS ZeroData
FROM tblLive_TrendLog_15Min
WHERE ISNULL(ElapsedValue, 0) = 0
GROUP BY CAST(DATEPART(yyyy, UTCTimeStamp) AS VARCHAR(4)) + '-'
+ CAST(DATEPART(mm, UTCTimeStamp) AS VARCHAR(2)) + '-'
+ CAST(DATEPART(dd, UTCTimeStamp) AS VARCHAR(2)) + ' '
+ CAST(DATEPART(hh, UTCTimeStamp) AS VARCHAR(2)) + ':00:000 - '
+ CAST(DATEPART(yyyy, UTCTimeStamp) AS VARCHAR(4)) + '-'
+ CAST(DATEPART(mm, UTCTimeStamp) AS VARCHAR(2)) + '-'
+ CAST(DATEPART(dd, UTCTimeStamp) AS VARCHAR(2)) + ' '
+ CAST(DATEPART(hh, UTCTimeStamp) AS VARCHAR(2)) + ':45:000'
When I run this query, it is going to display:
HourlyTime ZeroData NULL
2013-6-8 23:00:000 - 2013-6-8 23:45:000 0 40
2013-6-8 3:00:000 - 2013-6-8 3:45:000 0 52
2013-6-8 7:00:000 - 2013-6-8 7:45:000 0 52
2013-6-9 3:00:000 - 2013-6-9 3:45:000 0 52
2013-6-9 4:00:000 - 2013-6-9 4:45:000 0 52
2010-1-1 12:00:000 - 2010-1-1 12:45:000 0 36
2010-1-1 13:00:000 - 2010-1-1 13:45:000 0 27
2010-1-1 15:00:000 - 2010-1-1 15:45:000 0 30
Basically it is calculating the zero and null values per hour. If you want to know more about it this is the link:
SQL Programming combining 4 rows into 1 and adding 3 columns
Now, I just want to add another column to that query that would calculate
if there are any constant values then just display the number of the constant values (should be between 0 and 3) for example if the value at 2013-05-4 10:30 has the same value at 2013-05-4 10:15 then should be 1 in the ConstantData column. basically, compare the value to the previous value every 15 minutes.

Answer 1

I believe this is a duplicate question, but just wanted to point out that with SQL 2012 you could greatly simplify your query with the FORMAT function:
SELECT FORMAT(UTCTimeStamp ,'yyyy-MM-dd hh:00:000 - yyyy-MM-dd hh:45:000 ')AS HourTime ,
SUM(CASE WHEN ElapsedValue IS NULL THEN 1
ELSE 0
END) AS NoData ,
SUM(CASE WHEN ElapsedValue = 0 THEN 1
ELSE 0
END) AS ZeroData
FROM tblLive_TrendLog_15Min
WHERE ISNULL(ElapsedValue, 0) = 0
GROUP BY FORMAT(UTCTimeStamp ,'yyyy-MM-dd hh:00:000 - yyyy-MM-dd hh:45:000 ')