Applying the DSTv21 update for the Oracle Database (Doc ID 1583376.1)

Last updated on MARCH 16, 2021

Applies to:

Oracle Database - Standard Edition - Version 10.1.0.5 to 12.1.0.2 [Release 10.1 to 12.1]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.

Purpose

Proactive backports of the RDBMS DSTv21 <patch 17432124> are done to
* 12.1.0.1, 11.2.0.4, 11.2.0.3 , 11.2.0.2 and 11.1.0.7 for the following platforms: Linux X86, Linux X86-64 , Microsoft Windows X86 (32-BIT) , Microsoft Windows X86-64 (64-BIT) , Oracle Solaris on Sparc (64-BIT) , Oracle Solaris on Intel X86-64 (64-BIT) IBM AIX on Power Systems (64-BIT) , HP-UX Itanium (64-BIT), HP-UX PA-RISC (64-BIT) .
* 11.2.0.2 for HP OpenVMs on Itanium and Alpha.

Please log a SR if you need a backport to a platform or current version not mentioned.
Note that backports to 11.1.0.7 are available for download only for customers with a valid Extended Support . See <Note 412160.1> , section "G) For what versions are DST patches provided / there is no DST version X for my Oracle RDBMS version?"
Please consult your Sales representative to enroll in an Extended Support contract if required.

Proactive backports of the OJVM DSTv21 <patch 17443054> are done for 12.1.0.1 , 11.2.0.4 , 11.2.0.3. Other supported versions can be requested .
The OJVM DST patch is platform generic.

The RDBMS DSTv21 update includes the timezone information from the IANA ( http://www.iana.org/time-zones ) data tzdata2013e.tar and contains all previous Oracle RDBMS DST updates.
The OJVM DSTv21 update includes the timezone information from the IANA (http://www.iana.org/time-zones ) data tzdata2013e.tar and contains all previous Oracle OJVM DST updates.

This is archived content. The note covers the "DSTv21" update, newer DST updates are available.
Please see <Note 412160.1> Updated Time Zones in Oracle Time Zone File patches for information on the newer DST patches.

All DST patches are always cumulative, which means they contain also ALL the previous DST changes / corrections.
This means that:

if there is a requirement to apply DST version 21 it's a good idea to apply the latest available for your Oracle RDBMS version seen the newer DST patch this will have the same fixes and more. *
a newer DST patch for a certain RDBMS version can be used if the older DST patch is not available for this version (for example using DSTv22 instead of using DSTv21 for 12.1.0.1). *
any application that works correctly with DST version x will work fine with a database using a DST version higher than DST version x **
the database and client DST version does not need to be the same. If a client uses DSTv4 for example (and all used timezones by the application are correct in DSTv4) then there is no problem using this client against a database using a higher DST version.
in 11.1.0.7 and lower Optach will report a conflict when applying a new DST patch when an older is already installed, this can be ignored. There is no need to ask for a "merge" seen the newer dst patch has already all the fixes of the old one.
There are no "PSU DST patches" , for example an Oracle DST patch for 11.2.0.4 can be applied (manually or using Opatch) on *any* 11.2.0.4 psu (same goes for any other Oracle RDBMS version)

* When doing an Oracle RDBMS version upgrade there might be a requirement to apply an exact DST patch/version on the new Oracle RDBMS version home , check the notes in point C.1.a) and C.1.b) of <Note 412160.1> Updated DST transitions and new Time Zones in Oracle Time Zone File patches.
** This statement is true for DSTv4 and higher. The only exception are very old DST versions like 1, 2 or 3 and timezones are actually used (!) in the application.

In 11gR2 and higher the time to update to a new RDBMS DST version is depending 99% on the dataset size, not the target DST version.
For example if the current RDBMS DST version 14 then going from DSTv14 to DSTv21 will take the roughly the same amount of time as going from DSTv14 to DSTv21 .

Compared to DSTv20 this is the list of updated timezones in DSTv21 for non historical dates ( meaning update to the timezone after 1970):

Africa/Casablanca, America/Argentina/San_Luis, Pacific/Fiji, Asia/Jerusalem, Asia/Tel_Aviv, Israel

Scope

This note will give an overview on what checks to perform before applying the DSTv21 update.

Please note that SYSDATE is NOT affected by "Oracle DST patches" seen SYSDATE is purely depending on the OS to get the time.
So even an "unpatched database" will return a correct SYSDATE if the server (OS) time is correct.
For "sysdate" you do not need any DST patch <Note 227334.1> Dates & Calendars - Frequently Asked Questions
For more information about Timestamp with (local) Time Zone please check <Note 340512.1> Timestamps & time zones - Frequently Asked Questions