During Oracle 19c upgrade you may have to resolve the below required actions before upgrading the database

Complete any pending DST update operation before starting the database upgrade.
      There is an unfinished DST update operation in the database.  It's current state is: DATAPUMP(2)
      There must not be any Daylight Savings Time (DST) update operations
      pending in the database before starting the upgrade process.
      Refer to My Oracle Support Note 1509653.1 for more information.

 

You can check the status from the below query

SQL> SELECT PROPERTY_NAME, SUBSTR(property_value, 1, 30) value
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME LIKE 'DST_%'
ORDER BY PROPERTY_NAME; 
 

PROPERTY_NAME					VALUE

------------------------                        ------------------------------------

DST_PRIMARY_TT_VERSION				18
DST_SECONDARY_TT_VERSION			3
DST_UPGRADE_STATE				DATAPUMP(2)


 

SOLUTION –

Executed the following queries 2 times because there were 2 data pump jobs – DATAPUMP(2).

SQL>  ALTER SESSION SET EVENTS '30090 TRACE NAME CONTEXT FOREVER, LEVEL 32';

Session altered.


SQL> exec dbms_dst.unload_secondary;

Succeed in unloading the secondary timezone data file.
PL/SQL procedure successfully completed.


SQL> ALTER SESSION SET EVENTS '30090 TRACE NAME CONTEXT FOREVER, OFF';

Session altered.

 

Check the status of your DST

SQL> SELECT PROPERTY_NAME, SUBSTR(property_value, 1, 30) value
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME LIKE 'DST_%'
ORDER BY PROPERTY_NAME;

 
PROPERTY_NAME					VALUE

------------------------                        ------------------------------------

DST_PRIMARY_TT_VERSION				18
DST_SECONDARY_TT_VERSION			3
DST_UPGRADE_STATE				NONE

 

So, we are now fine with proceeding with the UPGRADE