Oracle Database Upgrade to 12c (In a Fail Safe Environment)

This a step-by-step detailed procedure for upgrading one Oracle Database 11gR2 (11.2.0.4) on Windows Server 2012 to the latest version 12c (12.1.0.2) with the latest available Windows Bundle Patch. The database is configure with Fail Safe (Active/Passive) cluster to provide some sort of high availability. This is an actual live upgrade for one of my … Continue reading Oracle Database Upgrade to 12c (In a Fail Safe Environment)

Why Query is not using the Index?

This post answers the following specific question:                 Why “distinct query” is not using the index (in some cases)? Let us try the following test case: Create sample table “t_distinct” and add an index to the “ID” column and collect statistics for table and index: Let us run the following basic query: It is clear … Continue reading Why Query is not using the Index?

The beauty of Visualization

I’m going to just touch this huge topic. I may post many other detailed posts about specific visualization techniques. This is just a brief introduction to get the feeling of how visualization can help a DBA in his daily activities. Let us start by example: If you want to query the database about how many … Continue reading The beauty of Visualization

The Power of the Oracle Trace Files

Although I had different topics planned for my first blog, but I just received this client issue this morning, and I decided to share it with you to explain how to take advantage of the powerful information contained in the oracle trace files. What is the issue? I received a call from one of my … Continue reading The Power of the Oracle Trace Files