Sunday, November 3, 2013

Deprecated Features in 12c DB

For deprecated parameters,

SQL> SELECT name from v$parameter
         WHERE isdeprecated = 'TRUE' ORDER BY name;

 Some deprecated parameters


Views deprecated

Deprecated DBMS_NETWORK_ACL_ADMIN PL/SQL package Procedures

The following procedures from the DBMS_NETWORK_ACL_ADMIN PL/SQL package are deprecated:


Oracle Streams and Advanced replication are deprecated too.
Raw storage devices desupported -- Any datafiles have to be moved to ASM,CFS or NFS.
Oracle restart NOT available even for single-instance systems, though ASM comes as part of Grid Infra for stand alone and cluster systems.

If upgrading or to 12c with OCFS/RAW devices, then first upgrade to 11.2 and migrate OCFS to ASM and then upgrade to 12c.

12C Database -- Features for a DBA during Upgrade

1)preupgrd.sql script replaces the utlu121s.sql script

This new utility provides fixup scripts to address issues that might be present both before and after the upgrade.

During the pre-upgrade phase, you can interactively run fixup scripts to resolve issues that are found.
 Post-upgrade fixup scripts are generated depending on the results of the upgrade process

2)The catupgrd.sql Upgrade Utility has been replaced with the new Parallel Upgrade Utility
You can run upgrade scripts and processes in parallel, taking full advantage of CPU capacity and shortening the upgrade time.
You can choose to upgrade your database in parallel or serial mode. In earlier releases, only serial mode was available,
which meant that the upgrade scripts and processes ran one after the other, regardless of how much CPU capacity was available.

3)DBUA Can Be Restarted During the Upgrade Process

New Oracle Recovery Manager (RMAN) support and Guaranteed Restore Point features
DBUA automatically creates a Restore Point.
–If an error occurs while DBUA during pre-upgrade steps, including backup and restore and listener migration, then you can restart DBUA.
–If post-upgrade steps fail due to encountering an error, then DBUA displays the manual steps for you to finish the upgrade.
 If the post-upgrade steps stop, then you can defer the saved post upgrade steps to finish the upgrade manually.
 Post-upgrade steps include moving data, post migration processing, upgrading the time zone file, or configuring Oracle Enterprise Manager.

¦The option to use Oracle RMAN to restore your database in case the upgrade fails has been improved in this release.

In certain cases, DBUA now enables you to restore your database from your own backup.
¦With RMAN backup, DBUA supports backing up of databases that use Oracle Automatic Storage Management (Oracle ASM).

4)Enhanced Pre-Upgrade and Post-Upgrade Summary Report
DBUA generates HTML reports before and after the upgrade. These reports include component status,
and also provide the ability to drill down to database objects, including invalid objects where an action to fix a problem might be available

5)Pluggable Databases
One of the key benefits of this new multitenant architecture is that you can upgrade or apply a patch to a CDB
and the upgrade or patch is implemented on all the PDBs within that CDB. This greatly simplifies administration for upgrading.

6) Oracle XML Database is Installed When You Upgrade

Oracle XML Database (Oracle XML DB) is now a mandatory component of Oracle Database.
You cannot uninstall it, and there is no option not to include it when you create a new database.
If during the upgrade, Oracle XML DB is not found, then Oracle XML DB is automatically loaded into the SYSAUX tablespace.
The upgraded Oracle Database includes Oracle XML DB.

7) Deprecation of catupgrd.sql Script
If you choose to run the catupgrd.sql script instead of running, doing so now requires an additional input parameter as follows:
SQL> catupgrd.sql PARALLEL=NO

8)Desupport of Oracle Enterprise Manager Database Control
Oracle Enterprise Manager Database Control is desupported and is no longer available.

Oracle introduces Oracle Enterprise Manager Database Express (Oracle EM Express) as a replacement.
Oracle EM Express is installed when you upgrade to Oracle Database 12c.

Upgrade Path considerations
11gR2 --> first to or later -->12.1
11gR1 --> first to or or later -->12.1
10g  --> or later -->12.1
9i --> and then to or -->12.1

Saturday, July 6, 2013

Exadata Offloading

Off loading is a process within Exadata servers where the data to be processed will be off loaded from database server to the storage server and part of the SQLstatements would be processed on storage servers.

Off loading has other benefits like reduction of CPU usage , reduction of Disk access time at Storage layer , but primary goal of Off loading is to reduce the Volume of data transferred from Storage to DB servers.

In Normal database, if a row is fetched from single column of a table, the whole block has to read in which the row exists,Off loading reduces this transfer of unnecessary data between storage and DB.

Exadata is though a Hardware & software combination on the whole, Software benefits be-little the benefits provided by Hardware.

cell_offload_processing is one of the Exadata parameters which reduces the processing time of a query/scan. True/False is the value it takes.