Oracle database downgrade from 11.2.0.3 to 10.2.0.4 and timezone files

Question

Hi,
I would like to test downgrade process through the scripts (@catdwgrd.sql). Oracle documentation http://docs.oracle.com/cd/E18283_01/server.112/e17222/downgrade.htm
says
"2.If you previously installed a recent version of the time zone file and used the DBMS_DST PL/SQL package to upgrade TIMESTAMP WITH TIME ZONE data to that version, then you must install the same version of the time zone file in the release to which you are downgrading. For example, the latest time zone files that are supplied with Oracle Database 11g Release 2 (11.2) are version 14 as of this printing. If after the database upgrade, you had used DBMS_DST to upgrade the TIMESTAMP WITH TIME ZONE data to version 14, then install the version 14 time zone file in the release to which you are downgrading. This ensures that your TIMESTAMP WITH TIME ZONE data is not logically corrupted during retrieval. To find which version your database is using, query V$TIMEZONE_FILE"
1) In my case, I used DBMS_DST and now the version if the time zone file is 14. If I have to go back to 10.2.0.4, Should i copy the files to $ORACLE_HOME/ORACORE/ZONEINFO (where $ORACLE_HOME is 10.2.0.4)?
2) If my Oracle 10.2.0.4 is shared with multiple instances, will i introduce risk for other databases running on the same oracle home when I copy the files?
3) What other steps should I do other than copying the version 14 files into this directory?
Thank You
Sarayu

Answer 1

user13312943 wrote:
Hi,
I would like to test downgrade process through the scripts (@catdwgrd.sql). Oracle documentation http://docs.oracle.com/cd/E18283_01/server.112/e17222/downgrade.htm
says
"2.If you previously installed a recent version of the time zone file and used the DBMS_DST PL/SQL package to upgrade TIMESTAMP WITH TIME ZONE data to that version, then you must install the same version of the time zone file in the release to which you are downgrading. For example, the latest time zone files that are supplied with Oracle Database 11g Release 2 (11.2) are version 14 as of this printing. If after the database upgrade, you had used DBMS_DST to upgrade the TIMESTAMP WITH TIME ZONE data to version 14, then install the version 14 time zone file in the release to which you are downgrading. This ensures that your TIMESTAMP WITH TIME ZONE data is not logically corrupted during retrieval. To find which version your database is using, query V$TIMEZONE_FILE"
1) In my case, I used DBMS_DST and now the version if the time zone file is 14. If I have to go back to 10.2.0.4, Should i copy the files to $ORACLE_HOME/ORACORE/ZONEINFO (where $ORACLE_HOME is 10.2.0.4)?
No - you should not copy files from the 11gR2 HOME to the 10.2.0.4 HOME - instead apply patch 9742718 to the 10.2.0.4 HOME (which corresponds to v14 of the DST patch)
Updated DST transitions and new Time Zones in Oracle Time Zone File patches [ID 412160.1]
2) If my Oracle 10.2.0.4 is shared with multiple instances, will i introduce risk for other databases running on the same oracle home when I copy the files?
You will need to follow steps in 9742718 for all of the databases running out of the 10.2.0.4 HOME
3) What other steps should I do other than copying the version 14 files into this directory?
See above
Thank You
SarayuHTH
Srini