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Multitenant database

Hot Clone of a Remote PDB in a Dataguard Environment 19c

Introduction In Oracle Database 19c, if you have a Dataguard Configuration of a multitenant database, and you want to clone a pluggable database from a remote server to your primary, then you have to mind that the dataguard mechanism is about applying redo, not copying datafiles : After you execute the clone, the new cloned pluggable will be useless on… 

Migrating Non-CDB to Multitenant

By Mouhamadou Diaw Dealing these last days to database migration with a customer, I write this blog to describe the main tasks The context is to migrate databases to a new infrastructure. Below the configuration Source : Linux Suse in a non-multitenant architecture Target : Oracle Enterprise Linux 8 with multitenant The database version is Oracle 19c Installing Oracle Binaries… 

Multitenant vs. schema based consolidation

By Franck Pachot . If you want to install multiple instances of a software, for example you host the ERP for several companies or subsidiaries, you have 3 solutions: have one database and multiple schema have multiple databases have one database and multiple pluggable databases Of course, this is exactly the reason for pluggable databases: multitenant. You have good isolation… 

12c: shutdown abort a PDB?

By Franck Pachot . Can we shutdown abort a PDB? Let’s try: SQL> show con_id CON_ID —————————— 3SQL> shutdown abort; Pluggable Database closed. But is it really a shutdown abort? The shutdown abort we know in non-CDB – or in a CDB from CDB$ROOT – is used when the instance cannot checkpoint before closing the file. It leaves the files… 

Oracle multitenant dictionary: rowcache

By Franck Pachot . I’ve not finished with my investigation on 12c multitenant dictionary. Here, I’m checking how metadata links are managed by the dictionary cache (aka rowcache). As I did previously, I’ll create a metadata link function in my lab environment (this is not for production. For the moment metadata/object links are supported only for oracle objects). SQL> connect… 

Stay with non-CDB or go to CDB?

By Franck Pachot . This is a question that starts to be raised quite frequently. Oracle released the multitenant architecture 1.5 year ago. And now says that the previous architecture – known as non-CDB – is deprecated. What does it mean? Do we have to go to the CDB architecture even if we don’t want to use/pay multi-tenant? It started… 

Oracle 12c: comparing TTS with noncdb_to_pdb

By Franck Pachot . How to migrate from non-CDB to CDB? Of course all known migration methods works. But there is also another solution: upgrade to 12c if necessary and then convert the non-CDB to a PDB. This is done with the noncdb_to_pdb.sql which converts a non-CDB dictionary to a PDB one, with metadata and object links. But do you… 

When Oracle resets session statistics

By Franck Pachot . During our Oracle 12c New Features workshop I had a very good question about whether the session statistics are reset or not when doing ALTER SESSION SET CONTAINER. My initial thought was that they were not reset because it’s the same session (same SID and SERIAL#). But when I’m not 100% sure about something, I test… 

12.1.0.2 CDB views are now using CONTAINERS()

By Franck Pachot . I’ve blogged about multitenant internals at the time when 12.1.0.1 was just released. Something has changed in 12.1.0.2 and blogging about it was in my todo list for a long time. Now the occasion to do it has been triggered by a question on Oracle Forums about CDB_DATA_FILES not showing PDB$SEED datafiles because there is an… 

Oracle 12c CDB – metadata & object links internals

By Franck Pachot . Warning: this is only geek stuff about internals on multitenant database dictionary, metadata, and object links. It has nothing to do with the operations that you can do on your database. Don’t try that in production or you can corrupt the whole dictionary. In 12 multitenant database (aka CDB) we know that each pluggable database is… 

Oracle Database 12c : démarrage automatique des Pluggable Databases

Dans ce blog post, nous allons nous intéresser à la gestion des PDBs (Pluggable Database) dans Oracle 12c. Plus exactement, nous allons nous pencher sur l’arrêt et le démarrage automatiques des PDBs en utilisant le Server Control (srvctl) du Grid Infrastructure de la 12c. Le contexte Au préalable, il faut avoir installé Grid Infrastructure et créé une CDB (Container Database)… 

Oracle Database 12c: PDBs not fully transportable yet

One of the benefits of the new Oracle multi-tenant database option is to create a kind of cloned environment through simple statements. This post will focus on the creation of pluggable database through a database link. The reason of this topic is that I am currently developing an advanced RMAN cloning procedure for 11g and this new 12c feature might…