Oracle database 12c upgrade to 19c

oracle

I was asked to advise some business analyst on migration from Oracle DB 12c to 19c. The thing is I have never used or done anything related to Oracle DB. From my experience with MSSQL during upgrade I know that some features became deprecated hence it required a bit of manual work for example re write custom made stored procedures, there were some issues with indexes and etc..

The good thing with MSSQL was it told you before upgrade what issues you will encounter and what is deprecated. Can you do check it similarly in Oracle Db aswell?

Also, please share your upgrade stories, did it went smooth? Did you encountered any issues afterwards? What should be kept in mind (that might break after upgrade) before upgrading? Also I would appreciate any related articles/videos/etc…

Best Answer

Upgrading 12c to 18c or 19c should not be a problem. I don't think that 19c is that different from 12c. The dbua tool should be able to do the upgrade. You still need to test with a test database. But running the dbua tool should work. Going from pre-12c to 19c is a much bigger issue depending on what features are used.

Related Solutions

Oracle build_plan_xml visualizer

You can use dbms_xplan.display_plan to get text, xml, html or 'active' output as a clob:

select dbms_xplan.display_plan(format=>'ALL', type=>'HTML') from dual;

select dbms_xplan.display_plan(format=>'ALL', type=>'ACTIVE') from dual;

Html is similar to the text output, but the 'active' type is quite different:

Active reports have a rich, interactive user interface akin to that found in Enterprise Manager while not requiring any EM installation. The report file built is in HTML format, so it can be interpreted by most modern browsers. The code powering the active report is downloaded transparently by the web browser when the report is first viewed, hence viewing it requires outside connectivity.

Upgrade scenario: Oracle 8.0.5.0.0 to Oracle 12c

There are multiple solutions to this problem but the driving issues are cost, allowable downtime and complexity.

Golden Gate could be purchased with a one year license and will do a zero downtime upgrade from Oracle 8i to 12. You still have to upgrade from 8.05 to 8i.
Your life could be simplified by using VmWare P2V to convert the machine to a virtual machine without any downtime. This method allows you to:
- get your production database on better hardware which should improve the speed of most operations
- allows you to make a copy of the machine, put it on a different subnet and start testing various strategies
I have imported schemas from our Oracle 8i database directly into Oracle 11.2 without issues. Your mileage may vary depending on character sets, licensed features and any unorthodox strategies your programmers have in the PL/SQL code.

One method that could be easily tested:

buy a new server with some serious hardware like 32GB RAM, install VMWare Esxi
convert your old machine to a virtual
create a development copy of the Oracle 8.05
install another virtual machine with Oracle 12
install another virtual machine with Oracle 10XE or 11XE
take snapshots of all the machines with no changes
take an export of the 8.05 development, import into Oracle 10XE or 11XE, test and verify
data pump to the 12 database
verify the data on 12 and offline the 8.05 and oracle 10XE or 11XE

This method needs downtime. A weekend should be more than adequate and only costs you a new server, Oracle 12 licence and some VMWare software licenses. Keep in mind that testing and verification can take more time than importing the data.

Best Answer

Related Solutions

Oracle build_plan_xml visualizer

Upgrade scenario: Oracle 8.0.5.0.0 to Oracle 12c

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