Oracle Technology Space to Share: July 2013

What is meant by pluggable databases?

With Multitenant you can have multiple pluggable databases - PDBs ("tenants") plugged into a single multitenant container database (CDB). Consolidate to support more applications per server. Manage many as one. Move PDBs between CDB to move between SLA tiers - unprecedented agility. No application changes required. More information upcoming in webcast.

When is 12c going to be available/supported on the exadata systems?

Oracle Database 12.1 is supported on Exadata. The minimum Exadata storage server software version required to run an Oracle 12.1 database is 11.2.3.2.1. You can also run a mix of 12.1 and 11.2 databases on Exadata. All features of the Oracle Database 12.1, including the multitenant pluggable databases are supported on Exadata. However, please note that the 12.1 smart scans will not filter rows in the Exadata storage and the 12.1 IORM plans will not be enforced in the storage. These limitations will be removed in a future Exadata storage server software version 12.1.1.1.0. Please look at the MOS note 1537407.1 for details. All other Exadata storage features like HCC, Smart Flash Cache, Smart Logging work as before.

12c pluggable databases, what that mean?

Stay tuned. Details will be explained in a few minutes. Also, much more info at: http://www.oracle.com/multitenant explain what multitenant means

Can migration be done one pluggable to another pluggable set?

Yes, migration between multitenant container databases (CDB) is supported. This gives us great agility, for example in migration between SLA tiers.

How SGA would be managed with mutiple pluggable database ?

The SGA is shared across the entire CDB. This shared overhead allows us to achieve maximum consolidation density.

Is pluggable database a chargeable option, and if so can we deploy 12c without using PDB?

Yes, Oracle Multitenant is a licensed option for Oracle Database 12c Enterprise Edition. However, you can deploy Oracle Database 12c in the so-called non-CDB architecture, just as before.

Tom, currently I get 50% compression for compress for OLTP in 11gR2. Will we get better compression in 12c like RainStor products?

The core algorithms for OLTP Table Compression - now called Advanced Row Compression - haven't changed from 11g to 12c, so I don't expect that your compression ratios will change. However, you have options in 11g and 12c to increase compression, by using Oracle storage - Exadata, ZFSSA, or Pillar Axiom - which allows you to use Hybrid Columnar Compression (HCC). You can estimate the HCC compression ratios you will get even if you don't have Oracle storage by using the compression advisor.

Also, in 12c you can use Heat Map and Automatic Data Optimization to automatically move data to desired storage tiers and compression levels, with no downtime and no DBA scripting.

Is Oracle Multitenant option an additional licence cost?

Oracle Multitenant is a new option with Oracle Database 12c. The single tenant configuration - one PDB per CDB is a no cost configuration. Two or more PDBs per CDB require the Multitenant Option license.

how much data 12c can store?>500GB

12c can store as much data as 11g - depending on your block size, the maximum size of a single Oracle 12c db can range into multiple petabytes...

is there a limit on # of pluggable databases per container?

We support up to 252 PDBs per CDB.

Is "Heat Map and Automatic Data Optimization" a feature or an option?

Heat Map and Automatic Data Optimization are features of Oracle Database 12c that are part of the Advanced Compression Option.

I have download OWB but it is not working with 12c

Try looking at the posts on the OWB Blog: https://blogs.oracle.com/warehousebuilder/entry/oracle_database_12c and I would suggest posting question on the OWB forum https://forums.oracle.com/community/developer/english/business_intelligence/data_warehousing/warehouse_builder

Do we gain any PDB benefits by using the no cost one PDB per one CDB configuration, or does it just increase complexity?

No, this configuration simplifies patch application. Patch CDB2 and migrate PDB from CDB1 to CDB2 to apply the patch.

Is there any plan to extend HCC beyond Exadata,Pillar Axiom and ZFS on commodity hardware?

There are no plans to extend support for HCC beyond the existing Oracle storage platforms.

If one unplugs a DB and plugs into a different CDB can one still have access to the DB during the move of the DB from one CDB to another?

No. The database is inaccessible from an application perspective while unplugged.

Is Licensing impacted due to Container/tenant databases?

Oracle Multitenant is a new licensed option with Oracle Database 12c.

In Oracle 12c is it still available Tablespace Encryption?

Yes. Transparent Data Encryption is available in Oracle Database 12c. This enables you to do both tablespace and column level encryption.

Do DB links work in the same manner with 12c CDB/PDB as prior versions?

Functionally, DB links between PDBs work just as they did between databases in prior versions of Oracle. Some perfrormance enhancements have been implemented for DB Links between PDBs in a single CDB.

When we have multiple PDB under 1 CDB, are there any PGA/SGA settings where I control the amount of memory to allocate to a particular PDB?

No. All the PDBs share, and compete for, the same SGA. This is just the same as when customers do schema-based consolidation.

When upgrading, an existing database becomes a PDB. Right?

Not exactly. Upgrade to Oracle Multitenant is a 2-stage process.

1. Upgrade to Oracle Database 12c - non-CDB (the old architecture).

2. Adopt the non-CDB as a PDB. Step 2 is optional.

Does the base architecture will remain same or changed in 12c ?

We recommend the "Oracle Multitenant" technical whitepaper on OTN. An internet search for "Customer challenges addressed by Oracle Multitenant" finds it immediately. Despite what this section heading implies for the approach, the paper is very solidly technical. It aims for precision and completeness -- and not at all for brevity.

what is the main objective of Pluggable database concept..??

Reduce CapEx, Reduce OpEx, Increase Agility, No application changes required.

Can I migrate and run an 11gR2 DB into a Pluggable DB on 12c? Without change?

Yes. This is simple. You upgrade in place to a 12.1.0.1 non-CDB and then plug that in as a PDB. Then you run a single post-plug step. The time time takes is independent of the size of the former non-CDB.

Can you have different database Oracle versions within the same tenant?

The benefit of Oracle Multitenant is the flexibility and agility of consolidating the container database management system and abstracting that from the data contained in pluggable databases. This consolidation is enabled by ensuring that all pluggable databases plugged into a container database to be on the same version/patchset level.

Is there a 12c equivalent of grid Infrastructure?

There is Oracle Grid Infrastructure 12c with new features. Please, see: http://www.oracle.com/technetwork/products/cloud-storage/index-100339.html

How will the patching work when you have pluggable databases? Do they all have to have the same patch set applied?

The patch set level applies at the CDB level. All PDBs plugged into the CDB will be at the same patch set level. The beauty is that the patch only needs to be applied once - at the CDB level - and all tenants benefit. If you want to migrate individual PDBs to a new patch set level, use 2 CDBs, one at patch level x, the other at level x 1. Apply patches to individual PDBs by unplugging them from one CDB and plugging into the other one.

what is a typical size of an unplugged database, I would assume it is more than just an export. Is an unplugged database an improvment upon typical backup/recovery functionality?

A pluggable database consists of a set of schemas and tablespaces which contain the data and the meta information for this data that is in the data dictionary. All this is packaged together in a neat bundle so it can be moved (uplugged from one container database and plugged into another) and backed up and recovered independenly of other pluggable databases. We expect most customers will backup whole container databases rather than each pluggable database separately because it is much easier to do this. A major benefit of pluggable database is reduced management costs.

If CBD fails then all PBD fails then it will be single point of failure, so how can we deal with it. keep apart about HA for CBD

Active Data Guard or Data Guard provide the mechanism for preventing a CDB from being a potential for a single point of failure - each will maintain a synchronized replica of the CDB on seperate system and storage. There are also management efficiencies. Where before, if you had 50 independent databases, you would have 50 standbys to manage. With Oracle Multitenant, you have a single primary (the CDB) and a single standby to manage. For more on Data Guard see: http://www.oracle.com/technetwork/database/availability/active-data-guard-wp-12c-1896127.pdf. If you wish to do granular replication at the level of an individual pdb, then GoldenGate provides that answer: http://www.oracle.com/technetwork/middleware/goldengate/overview/index.html

Is GoldenGate a feature of 12c by default for replication?

Active Data Guard, Data Guard, and GoldenGate are all replication options for 12c. The first two provide simple, complete, one way physical replication with target able to be open read-only. The later provides advanced logical replication (subsets, bi-directional, transformations, many-to-one, etc) with target open read-write. See:http://www.oracle.com/us/products/database/options/active-data-guard/overview/index.html and http://www.oracle.com/technetwork/middleware/goldengate/overview/index.html

Can one CDB have primary PDB and its corresponding standby PDB?

Data Guard in 12c Release 1 works with Container Databases. So all the Pluggable Databases in a Container Database will be protected by Data Guard, When you add Pluggable Databases to a container database it is automatically protected by Data Guard which is a nice benefit.

what is the backup & recovery of CDB & PDB's ??

We expect you to run scheduled backups for the whole CDB to win the "manage as one" benefit. But you'll probably want to do point-in-time-recovery for a single PDB. So, yes, PDB PITR is supported!

Would each plugable database has their own undo and temp tablespaces ? or they share the same undo & temp tablespaces ?

Redo and undo are shared across the entire CDB.

is it possbile to backup PDB separatly and recover it?

Yes. We do support PDB PITR!

if we are going to have one CDB with many PDB, with just one SGA, does it means we will have more performance issue, contention, and etc.

Oracle Enterprise Manager 12c works in concert with Oracle Database 12c to ensure the highest performance and most optimal resource management. To learn more, visit http://www.oracle.com/us/products/enterprise-manager/index.html

In 12c CDB we are sharing undo & redo log files among CDB & PBD...what if current redo logfile get lost due to catastropic failure, in that case all the pluggable database will be unavailable. Isn't a drawback of 12c CDB feature?

You can protect a CDB against catastropic failures with Data Guard. All the PDBs in the CDB are protected. If you create new PDBs in the CDB they are automatically protected as well. This reduces management costs significantly because you don't need to setup Data Guard or other facilities like RAC for every new database to give it good HA protections

When many databases are consolidated with PDBs, during patching, can I choose which database to patch because I don't have common down time window?

There are two options for applying patches with Oracle Multitenant.

1. Apply patch at the CDB level. All PDBs will benefit.

2. Create a second CDB and patch that. When your application is ready to be patched, simply unplug the PDB fro the old CDB and move it to the patched CDB.

Is the command set for controlling the CDB able to shutdown all PDBs under a CDB?

The instance opens the CDB as a whole. You acn set the open mode (read-write, read-only, or "closed") for an individual PDB -- and you can make a different choice for this in each different RAC instance.

the solution he just described with no data loss for far async dataguard configs, is this different than traditional dataguard? Is there an additional cost?

the feature described is Far Sync. It is a feature of Active Data Guard (so primary sending and the standby receiving redo from Far Sync needs to be licensed for Active Data Guard) - you don't need a seperate license for the server that Far Sync runs on. It is very different in that the Far Sync instance has no data files, does not run recovery - it just forwards redo to a remote standby and enables zero data loss failover. See more about Far Sync in the technical white paper: http://www.oracle.com/technetwork/database/availability/active-data-guard-wp-12c-1896127.pdf

Any improvements to DatagUARD and Broker in 12C?

Very significant improvements, most notable is validate database command that automates extensive healt checks, particularly useful before executing switchovers. Also there is the concept of resumable switchover, to gracefully handle any unexpected errors during role transtions, see more in the technical white paper http://www.oracle.com/technetwork/database/availability/active-data-guard-wp-12c-1896127.pdf and on OTN at http://www.oracle.com/goto/dataguard

Does the new synchronous dataguard feature has distance limitation?

there is always a practical distance limitation between source and a synchronous destination. Fast Sync will extend that distance by taking standby disk i/o out of the round-trip time. Far Sync makes the distance between primary and standby unlimited for the purpose of performing a zero data loss failover to a remote standby - but the Far Sync instance will still have the usual distance considerations between it and the source (since it is like any other synchronous destination).

any enhancements to RMAN in oracle 12c?

Yes, look at the 12c RMAN Users Guide, "New Features & Changes". Table recovery from backup, cross-platform backup & restore, pluggable database backup & recovery are some of the new features.

Oracle Technology Space to Share

Friday, July 19, 2013

Database Opatch

Wednesday, July 17, 2013

Oracle Database 12c Introduction - Webcast Q & A