Online Datafile Move or Rename

Here I am going to discuss one of my favourite new feature of Oracle 12c which has taken the down time away from the DBAs while moving or renaming a datafile online. There is no requirement of any downtime during this operation

Oracle Segment Adviser Recommendations and Redo/Undo Generation During Segment Shrink

Since Oracle 10g, Oracle provided facility to reclaim the unused space from Tables and Indexes by using"ALTER TABLE <TABLE_NAME> SHRINK SPACE | COMPACT"  command.
Before we go through details of Oracle Segment Adviser Recommendations, it should be noted that during shrink space operation, a lot of undo and redo data is

Implementing Class of Secure Transport (COST)

To safeguard against security vulnerability (CVE-2012-1675) as published here, COST (Class of Secure Transport) parameter is used to restrict any remote instance to get registered with the listener running on a database server. This is done by adding a parameter SECURE_REGISTER_<LISTENER_NAME> = (TCP) in the listener.ora file

RMAN Backup Performance

Finishing an RMAN backup on time (fast) is usually what every DBA looks for. Here I would be discussing my experience of RMAN backup scenarios which I tested for speed and performance. Environment details are as follows.

Converting a Failed Over Standby Database Back to Standby Database

I have seen some articles on the internet for reinstating a primary database after a failover (using flashback database technology – if FLASHBACK RETENTION time has not exceeded), but I was not able to find a document to revert or reinstate a “failed-over” standby database (which has now become primary) back to a standby database (using FLASHBACK technology).

ORA-01624 log needed for crash recovery of instance

It is quite common to see the error ORA-01624 while dropping a redo log group. The full error text is similar to “log <log_group#> needed for crash recovery of instance <instance_name (thread #)”.

Reason
As we know that Log Writer (LGWR) has the responsibility to write

Tablespace Growth History and Forecast for 10g and 11g

Finding space usage of tablespaces and database is what many DBAs want to find. In this article I will explain how to find out space usage history and forecasting future growth of tablespaces. For 10g and 11g database growth history and forecast see script Database Growth History and Forecast for 10g and 11g.
For 12c and above; Tablespace and Database growth history and forecast, please use following scripts
Tablespace Growth History and Forecast for 12c and Above.
Database Growth History and Forecast for 12c and Above.

Error "[NS-20802] Grid Infrastructure Configuration Failed" During 11.2 RAC installation on Windows 2008R2

I faced error "[NS-20802] Grid Infrastructure Configuration Failed" during a 2 node Oracle 11.2 RAC installation on Windows 2008 R2 (64 bit). All prerequisites were checked and cluvfy also did not show any problem, but during installation,

Using Oracle Orion for IO Calibration

ORION is a tool provided by Oracle to calibrate the IO of storage you are planning to use for database server. Some salient features of this tool are as follows

·         Oracle provided tool which can be downloaded separately

Oracle Stats Gathering During Automated Maintenance Tasks Window

Problem Background
A few days back I faced a problem when I received slowness complaints from end users who use an application based on our 11.1.0.7 database. While investigating, I came to know that at 10:00 AM, a stats gathering job started which lasted for 45 minutes and during this window,