# https://oracle-base.com/articles/misc/update-database-time-zone-file#upgrade-time-zone-file-multiteanant


# check current time zone version

select * from V$TIMEZONE_FILE;
select TZ_VERSION from REGISTRY$DATABASE;


-- qyery dst_check.sql -----------
COLUMN property_name FORMAT A30
COLUMN property_value FORMAT A20

select 
    property_name, property_value
from
    DATABASE_PROPERTIES
where  
    property_name like 'DST_%'
order by 
    property_name;
----------------------------------

# latest available version of the timezone
select DBMS_DST.GET_LATEST_TIMEZONE_VERSION from dual;


# prepare for the upgrade (optional)

DECLARE
  l_tz_version PLS_INTEGER;
BEGIN
  l_tz_version := DBMS_DST.get_latest_timezone_version;

  DBMS_OUTPUT.put_line('l_tz_version=' || l_tz_version);
  DBMS_DST.begin_prepare(l_tz_version);
END;
/

# execute dst_check.sql
# DST_UPGRADE_STATE should change from NONE to PREPARE

# clean tachnical tables
truncate table SYS.DST$AFFECTED_TABLES;
truncate table SYS.DST$ERROR_TABLE;


# find tables and errors affected by the upgrade
exec DBMS_DST.FIND_AFFECTED_TABLES;

select * from SYS.DST$AFFECTED_TABLES;
select * from SYS.DST$ERROR_TABLE;

# perform necessaty checks and finish the prepare step if you want to go ahead with the upgrade
exec DBMS_DST.END_PREPARE;

# Note: for a CDB, TZ should be upgrade in each container 

# restart the database in UPGRADE mode

# BEGIN upgrade
###############
SET SERVEROUTPUT ON
DECLARE
  l_tz_version PLS_INTEGER;
BEGIN
  SELECT DBMS_DST.get_latest_timezone_version
  INTO   l_tz_version
  FROM   dual;

  DBMS_OUTPUT.put_line('l_tz_version=' || l_tz_version);
  DBMS_DST.begin_upgrade(l_tz_version);
END;
/

# restart the database 

# END upgrade
#############
SET SERVEROUTPUT ON
DECLARE
  l_failures   PLS_INTEGER;
BEGIN
  DBMS_DST.upgrade_database(l_failures);
  DBMS_OUTPUT.put_line('DBMS_DST.upgrade_database : l_failures=' || l_failures);
  DBMS_DST.end_upgrade(l_failures);
  DBMS_OUTPUT.put_line('DBMS_DST.end_upgrade : l_failures=' || l_failures);
END;
/

# restart the database 


# following queries can be used to check the progress of the TZ upgrade table by table
-- CDB
COLUMN owner FORMAT A30
COLUMN table_name FORMAT A30

SELECT con_id,
       owner,
       table_name,
       upgrade_in_progress
FROM   cdb_tstz_tables
ORDER BY 1,2,3;

-- Non-CDB
COLUMN owner FORMAT A30
COLUMN table_name FORMAT A30

SELECT owner,
       table_name,
       upgrade_in_progress
FROM   dba_tstz_tables
ORDER BY 1,2;

# Note: in 21c, the following parameter is supposed tu avoid database restart during TZ upgrade
# in my test it does not worked
alter system set timezone_version_upgrade_online=true scope=both sid='*';


-- restart PDB$SEED in UPGRADE mode
alter pluggable database PDB$SEED close immediate instances=ALL;
alter pluggable database PDB$SEED open upgrade instances=ALL;
show pdbs
alter session set container=PDB$SEED;
-- run BEGIN TZ upgrade procedure

-- restart PDB$SEED in READ-WITE mode
alter session set container=CDB$ROOT;
alter pluggable database PDB$SEED close immediate instances=ALL;
alter pluggable database PDB$SEED open read write instances=ALL;
alter session set container=PDB$SEED;
-- run END TZ upgrade procedure

-- restart PDB$SEED in READ-WITE mode
alter session set container=CDB$ROOT;
alter pluggable database PDB$SEED close immediate instances=ALL;
alter pluggable database PDB$SEED open instances=ALL;

-- check TZ and close PDB$SEED
alter session set container=CDB$ROOT;
alter pluggable database PDB$SEED close immediate instances=ALL;