By Franck Pachot . Now that 12.2 is there, in the Oracle Public Cloud Service, I can share the slides of the presentation I made for Oracle Open World: 12cR2 Single-Tenant: Multitenant Features for All Editions from Franck Pachot I’ll give the same session in French, In Geneva on November 23rd at Oracle Switzerland. Ask me if you want an…
By Franck Pachot . Oracle database 12.2 is there on the Database Cloud Service, in multitenant. In EE High Performance or Extreme Performance, you have the multitenant option: you can create 4096 pluggable database (instead of 252 in 12.1). If you are in lower services, you can create only one user PDB (not counting application root and proxy PDB). If…
By Franck Pachot . Here is, in my opinion, the most beautiful feature of the multitenant architecture. You know how I love Transportable Tablespaces. But here: No need to put the source in read/only No need to export/import the metadata logically No need for any option: available even in Standard Edition Standard Edition I am in Standard Edition here in…
By Franck Pachot . In multitenant you session can switch between containers. For example, since 12.1, a common user can switch explicitly between CDB$ROOT and any PDB with the ‘ALTER SYSTEM SET CONTAINER’. Any user connected to a PDB will also have it session switching implicitely when querying through metadata links and data links (new name for object links). In…
By Franck Pachot . Pluggable Databases are supposed to be isolated, containing the whole of user data and metadata. This is the definition of dictionary separation coming with multitenant architecture: only system data and metadata are at CDB level. User data and metadata are in separate tablespaces belonging to the PDB. And this is what makes the unplug/plug available: because…
By Franck Pachot . In a previous post, tribute to transportable tablespaces (TTS), I said that TTS is also used to move data quickly from operational database to a datawarehouse ODS. For sure, you don’t transport directly from the production database because TTS requires that the tablespace is read only. But you can transport from a snapshot standby. Both features…
By Franck Pachot . I’m preparing some slides about PDB security (lockdown) and isolation (resource) for DOAG and as usual I’ve more info to share than what can fit in 45 minutes. In order to avoid the frustration of removing slides, I usually share them in blog posts. Here is the basic concepts of CDB resource plans in multitenant: shares…
By Franck Pachot . It’s official, Larry Ellison made the announcement at first keynote and the database product team at oracle has released the version and the documentation publicly. Oracle Database Exadata Express Cloud Service is the ‘Cloud First’ environment for 12.2 Documentation Documentation is there: Cloud > Platform > Data Management > Exadata Express The 12.2 new features available…
By Franck Pachot . Database on ACFS is a long story. At first, the main reason for ASM was to bypass a filesystem layer that is not required by the database. ACFS was for the non-database files that had to be accessed by all cluster nodes. But then, storage vendors and other providers came with snapshots, compression and thin provisioning…
By Franck Pachot . On the Oracle Database Appliance, like on the Oracle public Cloud, you define the CPU capacity with ‘shapes’. On the latest ODA, the X6, we have a new interface to provision a database. Let’s look at the different shapes available. ODACLI You can provision a new database with the command line ODACLI which replaces the OAKCLI…
By Franck Pachot . When Oracle Multitenant came out in 12c, with pluggable databases, it was easy to draw them as USB sticks that you can plug and unplug to/from your Container Database (CDB). I don’t like this because it gives the false idea that an unplugged database is detached from the container. Containers In the Oracle documentation, the Concept…
By Franck Pachot . The previous post partly answered to the original question (why an object link to V$SESSION is refreshed only every 30 seconds): recursive queries on shared=object views. Now let’s see what is different with fixed tables. Disclaimer: this is research only. Don’t do that anywhere else than a lab. This is implicit when the title is ‘internals’.…
