ORA-19698

If you have encountered this ORA-19698  oracle error the first time, don't worry. Usually this happen when recovering a database to a host with a different database ID .
Solution: replace the redolog files located in  E:\oracle\product\10.2.0\oradata\yourSID of the host by the one of the incoming database. Smiles !!!

start oracle after shutdown

Have you shutdown your oracle database (shutdown immediate; ) and looking for how to restart your database ? Here are the four (04) secured steps to do so:

1.  connect as sysdba
2. startup mount;
3. alter database archivelog;
4. alter database open;
5. enjoy !

Group by not working in oracle

 Have you run into this trouble with grouping in oracle, especially after transferring your database into different system running obviously a different version of oracle ? Be cool.
Oracle introduced a hash-based GROUP BY in 10.2.  Previously, a GROUP BY operation involved sorting the data on the relevent columns, then accumulating aggregate results. 

What does it means ?

before 10.2 : select name , id from table group by id, name => will work

after 10.2 : select name , id from table group by id, name => will  not work
            but select name , id from table group by id, name order by  id, name => will work


To disable the hash-based group by using the following command under a user with sysdba' privilege:

> alter system set "_gby_hash_aggregation_enabled" = FALSE scope=BOTH;

> commit;

Turn on controlfile autobackup on in oracle

Because during the database recovery process it is very important to have the recent copy of the control file, RMAN provide you with the ability to automatically backup this file whenever there is a change in your database. However by default this feature is off so you have to turn on manually.

1. Start RMAN and connect to a target database and a recovery catalog (if used).
2. Check the status : rman>  SHOW CONTROLFILE AUTOBACKUP;
3. Turn it on:  rman> CONFIGURE CONTROLFILE AUTOBACKUP ON;
4. Check the status again, this time it should be on.
5. For more about RMAN configuration parameters, just type : rman > SHOW ALL;

Motivaitons as a Life perspective changer ?

It is commonly said that no wise old man would want to become younger. What does it really mean ? As life goes on we go through many ups and downs, success and failure. These series of events contribute to shape up us. Learning along this hard time make a till then naive person a wise man/woman. What you about those young one or old have not lived such scenarios. How can they learn ? They can learn from the wise one sayings. I have found some nice motivations that I would like to share with you today.