Oracle Job Scheduler runs my jobs, one hour earlier, (Daylight Saving Time related)

Problem:

Scheduler runs my jobs one hour earlier, which causes empty summary tables in ETL process.

Log Date                  2010/01/21 02:00:09.072642 +02:00

Required Start Date  2010/01/21 03:00:04.662096 +03:00

Actual Start Date      2010/01/21 03:00:00.000000 +03:00

BEGIN

SYS.DBMS_SCHEDULER.CREATE_JOB

(

job_name        => 'MYCHEMA.SR54'

,start_date      => SYSTIMESTAMP,

,repeat_interval => 'FREQ=DAILY;BYHOUR=3;BYMINUTE=0;BYSECOND=0'

,end_date        => NULL

,job_class       => 'DEFAULT_JOB_CLASS'

,job_type        => 'PLSQL_BLOCK'

,job_action      => 'GENERIC_SUMMARY.procprocessreport ( 54 );'

,comments        => 'trunc(sysdate+1)+3/24'

);

SYS.DBMS_SCHEDULER.enable (name => 'log_parallel_process_job');

END;

/

Cause:

Using SYSTIMESTAMP as start date is converted as for example:

start_date      => TO_TIMESTAMP_TZ('2009/08/05 15:14:24.499000 +03:00','yyyy/mm/dd hh24:mi:ss.ff tzr')

You can see it from the ddl script of this in TOAD.

Thus, it means that you are hard coding the daylight saving time.

For example in Turkey, DST is GMT +03:00, it means if you create this script in summer time it will be hardcoded as +03:00 and if it is in other than day light saving time(normal time), it will be +02:00 in Turkey.

Solution:

Using named timezone code solves the problem, it will automatically adjust the execution time for you. Do not forget that, it also prevents

BEGIN

SYS.DBMS_SCHEDULER.CREATE_JOB

(

job_name        => 'MYCHEMA.SR54'

 ,start_date => TO_TIMESTAMP_TZ('2010/01/21 10:00:00.000000 Turkey','yyyy/mm/dd hh24:mi:ss.ff tzr')

,repeat_interval => 'FREQ=DAILY;BYHOUR=3;BYMINUTE=0;BYSECOND=0'

,end_date        => NULL

,job_class       => 'DEFAULT_JOB_CLASS'

,job_type        => 'PLSQL_BLOCK'

,job_action      => 'GENERIC_SUMMARY.procprocessreport ( 54 );'

,comments        => 'trunc(sysdate+1)+3/24'

);

DBMS_SCHEDULER.enable (name => 'log_parallel_process_job');

End;

/

For further details, and thanks goes to below links:

http://forums.oracle.com/forums/thread.jspa?threadID=646581

You can find your Time Zone Names in Oracle® Database Globalization Support Guide:

For eample: http://download-uk.oracle.com/docs/cd/B28359_01/server.111/b28298/applocaledata.htm#i637736