Duplicate Database Using ‘FROM ACTIVE DATABASE’ clause – 11gR2

I was asked to duplicate a production database on a new server and as it was on 11gR2, it was time to use the best available option i.e., using 'from active database' clause.After doing a successful duplication i thought of putting it on blog as i observed and encountered few things which i wanted to …

enq: TX row lock contention and enq:TM contention

Recently, on a production system i observed number of sessions with "waiting" state and the event being "enq: TM contention" and the reason for it was something which i didn't knew earlier.So, i thought of writing on both 'TX' and 'TM' contention. Here i will discuss only few which i have observed are the common …

ORA-14452: attempt to create, alter or drop an index on temporary table already in use

After reading Hemant Sir's blog "GLOBAL TEMPORARY TABLEs and GATHER_TABLE_STATS " (http://hemantoracledba.blogspot.com/2011/01/global-temporary-tables-and.html) i tried the same on my system and again learned something new 🙂 Time to share it :). Session 1 --> Anand's session Session 2 --> SYS as sysdba Session 2 ========== 16:05:05 SYS@MATRIX> @session Username OSUSER SID SERIAL# SPID STATUS MODULE Term …

How to move table containing LONG or LOB columns?

Today a friend of mine asked me how to move a table having LONG datatype.As per him, when he fired alter table table_name move tablespace , he got "ORA-00997: illegal use of LONG datatype".In past, i had moved the tables to the other tablespace but had not faced this error.So, it was time to do …

2010 in review

The stats helper monkeys at WordPress.com mulled over how this blog did in 2010, and here's a high level summary of its overall blog health: The Blog-Health-o-Meter™ reads Wow. Crunchy numbers A helper monkey made this abstract painting, inspired by your stats. The average container ship can carry about 4,500 containers. This blog was viewed …

Creating Standby Database – 11gR2 using ” FOR STANDBY FROM ACTIVE DATABASE” clause

Year 2011 comes with 11gR2 for me 🙂 As the title says, here i will demonstrate one of the way to create standby database which i did on a 11gR2 version windows box.The primary and the standby exists on the same box. Primary DB Instance name - MATRIX Standby DB Instance name - MATSTDBY As …