Why use To_Localtime when analyzing IIS logs

Question

I've searched for several examples to analyze IIS logs using the Log Parser, taking time into account... For example, this query that shows the number of hits per hour:

SELECT 
QUANTIZE(TO_LOCALTIME(TO_TIMESTAMP(date, time)), 3600) AS Hour, 
COUNT(*) AS Hits 
FROM D:\Logs\*.log 
Group By Hour

However I cannot understand why use "TO_LOCALTIME"... Also, if there is a time difference (and a difference in results while using "TO_LOCALTIME" or not), how is that?... Thank you!

Answer 1

All IIS uses UTC for all times in its logs regardless of the time zone of the server, so to get your local time, you can use TO_LOCALTIME.

I guess if you are fine with UTC, you don't need to use TO_LOCALTIME.