There is a new feature listed in the docs as as “Support for PDBs with Different Character Sets, Time Zone File Versions, and Database Time Zones in a CDB”. I’ve already written about the PDB character set stuff and it is also listed separately as a new feature. The time zone stuff works in 12.1, so it doesn’t appear to be a 12.2 new feature. The different Time Zone File Versions functionality, as far as I can see, relates to OCI client connections to the server and was introduced in 11.2. With all that in mind, I’m really not sure what this listed new feature specifically relates to. If someone can clear that up for me I would be really grateful, as I’m wondering if I’ve just missed the point somewhere. 🙂
I’ve added these to the list of all my multitenant articles here.
Some things happened to me yesterday which I thought I would pass on, in case it helps others. This is not necessarily a criticism of the Multitenant architecture itself, but more about my misuse of it. 🙂
I’ve complained numerous times about the inclusion of the shared APEX installation used with the Multitenant option. I’m sure it is great for some companies that provide APEX as a service, but it’s not the right option for me. I would typically recommend removing it before you create a PDB, as described here. So what did I do yesterday? I banged out a script as a variant of a non-CDB build and totally forgot about the shared installation. When everything was finished I patted myself on the back, then noticed my mistake. 🙁 I had to remove the PDBs from 3 instances, remove the shared APEX installations, the recreate the PDBs. Luckily it was early on in the process, so it wasn’t a great drama. It would have been significantly more annoying if I hadn’t noticed for a few days!
Next up I nearly cloned a PDB, which would have left me with 2 PDBs in the instance, and potentially a big bill for the Multitenant option. I was literally about to hit the return key when I realised what I was doing. 🙁 Needless to say I immediately added a trigger to all my instances to prevent any future stupidity on my part. You can see what I did here. As I say in the article, I’m not sure if there is some hidden long term tracking of the maximum number of PDBs in a CDB, but I’m a paranoid type… 🙂
As an aside, I also noticed that when I add a new PDB to a CDB it takes Cloud Control 13c a long time to notice the PDB is there. I did try to give it a nudge by doing the following, but it didn’t seem to notice.
Highlight the CDB in the database target list.
Click the “Configure” button.
Scroll down and click the “Sync Pluggable Databases” button.
It didn’t recognise the change, even though it was clear in the V$PDBS and CDB_PDBS views. Not sure if this is normal or if I just got unlucky. Everything looks OK now… 🙂