important considerations for EBS database upgrade to 19C

 Nowadays, there is a huge demand for EBS DB upgrade to 19c because 19C database is the latest long term release. You can refer the below diagram on the Database releases and Support Timelines.

I did back to back EBS DB upgrade to 19c which you can refer in my previous posts https://samappsdba.blogspot.com/2020/12/upgrade-EBS-12.2-database-12c12.1.0.2-to-19c19.3-Part-1.html. Now, the purpose of this post is to make everyone aware of the different sort of issues which you can encounter while doing the upgrade and also, i have tried my best to provide the solutions. Also, i have  highlighted some basic terminologies which if known, will ease up the upgrade.

1. Source DB will become the PDB.

Your source Database will be converted into PDB and which then will be attached to CDB. So if your source DB sid is PROD, then your PDB will also be PROD.

2. Running hcheck.sql

This mainly reports the data dictionary issues and thus if you see any errors, you should seek an assistance from Oracle Support. This usually takes time, thus it is required to do this step in advance.

3. CDB listener

As part of 19c upgrade and multitenant conversion, the listener should be started with the CDB name.

4. Characterset Issue

While doing the upgrade, please note down the source characterset and make sure while creating the CDB, the same characterset options are choosen. If there are character sets mismatch, then you will get an error while doing the conversion to multitenant DB.

You can use the below query:-

select * from database_properties where PROPERTY_NAME in ('NLS_CHARACTERSET', 'NLS_NCHAR_CHARACTERSET');

 In order to know more about the various issues and their solutions, you can through the  metalink note 19c Database with Oracle E-Business Suite R12 Known Issues & Solutions (Doc ID 2662860.1)

 

I hope you find this note useful. Happy upgrade to 19c.