The non-CET timezone issue

**AndersMcNair** · 09-14-2009, 08:47 AM

I get different results when I run a transformation in Copenhagen (timezone GMT+1) and Kiev (timezone GMT+2) respectively. I have narrowed the cause down to the value of system variable "start date range (Transformation)" in cases where log table is empty.

When I run in Copenhagen "start date range (Transformation)" is 1900/01/01 00:00:00.000 but when run in Kiev it is 1900/01/01 01:00:00.000. A difference of one hour.

I have noticed that changing Date & Time settings in Windows affects the value (after restarting Kettle). I have also tried different databases in different timezones but it does not seem to matter.

Can anyone help me explain why this is happening?

Kettle version is 3.1.0 and DB connections are Oracle/JDBC.

Thanks

**dhartford** · 09-14-2009, 01:23 PM

Lo do I wish from a software development perspective there were no timezones...

Here is the list of culprits:
*Operating System timezone/time of Database Server
*Operating System timezone/time of ETL Server
*Timezone of database server itself (if it attempts to change default OS timezone, usually on a database instance).
*Timezone of JVM of ETL server (cluster beware).
*Timezone of JDBC connection to database server (could be changed, but adjusts based on JVM timezone, so be wary).
*And, lastly, the timezone of the data itself.

The 'quickest' way is to adjust your hours either forward or backward to ensure they are the same actual day (MM/dd/YYYY) despite the hours difference between the timezones.