Multitenant : Massive Changes in 19c and 20c

Is it safe to talk about this now? The announcement has happened and Mike Dietrich has posted about it, so I think so…

A couple of massive things have happened regarding the multitenant architecture in Oracle 19c and 20c.

19c

Prior to 19c, you were only allowed to have a single user-defined pluggable database (plus a root container and a proxy) without having to license the full multitenant option. I’ve been a big proponent of single-tennant or lone-PDB, but I can understand the reluctance of people to go that way, as it’s harder to realise the benefits, even though they do exist.

Oracle have now announced from 19c onward you can have 3 user-defined PDBs, without having the multitenant option. This is similar to what we got with 18c XE. As Mike points out, the documentation has already been changed to reflect this.

“For all offerings, if you are not licensed for Oracle Multitenant, then you may have up to 3 PDBs in a given container database at any time.”

Database Licensing Information User Manual

I think this is will be a massive boost for the uptake of the multitenant architecture. I’ve got some 19c stuff that will probably make use of this within days of me getting back to work!

!!!!!Amazing!!!!!

20c

Are you one of those people that have been saying, “Screw that multitenant stuff. I’m sticking with non-CDB architecture!” Good luck with that. In 20c the non-CDB architecture will be desupported.

You probably know the non-CDB architecture was deprecated since 12.1.0.2, but in 20c non-CDB is no longer an option, unless you are happy about running without support I guess.

This means your 20c upgrade will also include a migration to the multitenant architecture. What I would suggest is you start down that road today by moving to multitenant in 19c, then when you have to move to the next long term support release (2?c), you won’t be getting any surprises. What’s more, the 3 PDBs thing in 19c makes that all the more attractive!

If this announcement has made you panic, don’t worry. I’ve written a bunch of stuff about multitenant over the years, and there’s a YouTube playlist too.

Cheers

Tim…

PS. Smiles smugly to himself that he invested the time into learning multitenant from 12.1 onward…

PPS. I will be going through my existing articles amending any mention of licensing and PDB limits and desupport etc. Those changes won’t happen overnight. 🙂

Video : Multitenant : Hot Clone a Pluggable Database (PDB) in Oracle Database 12.2 Onward

Today’s video is a run through the hot cloning functionality introduced in Oracle 12.2 multitenant.

You might also be interested in this playlist.

If videos aren’t your thing, you can always read the articles, which contain more information.

The star of today’s video is Craig Shallahamer. Craig is a really dynamic presenter, and I think this is the only time you will ever see him standing still! 🙂

Cheers

Tim…

Multitenant Enhancements in Oracle Database 12.2 (Some More Articles)

The Oracle Database 12c Release 2 (12.2) learning process continues. I’m determined to get to the bottom of all this new multitenant stuff. 🙂

Here’s the latest batch of articles.

So the last one is actually for 12.1, but I hadn’t written about it already, so I added it.

I also updated this article to include the “CONTAINERS Hint” feature functionality.

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.

Cheers

Tim…

Multitentant (Pluggable Database) Videos

It’s been over 2 years since 12c was released and there still seems to be a lot of confusion about the pluggable database stuff. I think most people know the top-level concept, there’s only so many times you can see the memory stick analogy before it gets burned on your skull, but that doesn’t do much to help with the reality of working with it day-to-day.

I’ve written a whole bunch of articles on pluggable databases (listed here), but even then I think there is quite a bit of text for what in many cases is a feature that consists of a single statement. 🙂

I’ve recently been pushing out some videos on this stuff and I’ve got some more already recorded for release while I’m at OOW. Of course, the articles allow you to copy/paste your way through an example, but I think the videos give a more accurate representation of just how simple some of this stuff is from a functional perspective. If you are interested, all the multitenant stuff will be added to this playlist as it is released.

Cheers

Tim…

Oracle 12c Multitenant Option : CDBs and PDBs…

I started trying to play with the Oracle multitenant option (all that pluggable database stuff) a little while ago and gave up. It’s wasn’t that it was that difficult. More than anything my problem was I didn’t know what to focus on first. There is so much to it and it’s all interrelated, so you start to write about one small piece and before you know it your article has lost focus and is growing too big. As a result I decided to let it simmer in the background and start looking at some of the other smaller 12c new features first…

My next stumbling block was just about everything in 12c seems to relate back to pluggable databases in some way. So you either pretend it doesn’t exist and have gaping wholes in everything you write, or you have to bite the bullet and get to grips with pluggable databases. So back I came to pluggable databases…

Even with my new found commitment to getting to grips with it, I was still struggling to decide how to break this stuff up into manageable pieces so I could write concise articles and order my thoughts on this functionality. Writing is part of my learning process, so if I can’t see how to break down and structure the articles I’m a little lost. Then the recently released OCP syllabus came to the rescue. I always try to write revision notes for the OCP upgrade exam, so I decided the way they break it down will be my template. I’m probably going to write a separate article per bullet point, and try and keep them as directed as possible.

So the first couple of articles have gone live.

Now I’ve got a plan of attack I feel a lot happier.

As always, I will make multiple passes and keep adding things to articles as I encounter things of interest. It’s always a fine balance between being too brief on one hand or regurgitating the manual on the other. The important thing is the content constantly evolves.

The other thing to consider is the OCP syllabus is only a starting point. There is lots of cool stuff that is not on the OCP syllabus, so I’m not going to be a slave to it. As I’ve said before, the OCP syllabus is a nice framework to start you on your journey, but it is not the final goal, it’s just a stepping stone…

I’m not sure why I felt the need to write this little 12c mission statement. Probably to help me solidify in my head how I’m going to tackle the next 18 months while I’m getting to grips with this new version. So that’s the plan, until I come up with a better one… 🙂

Cheers

Tim…