Re: Explain SQL - RDBMS Tuning

> I am researching on a facility called 'Explain Plan', a database tuning tool
> available within Oracle. I am look for opinion on its usefulness as a Database
> Tuning Tool. Also I am looking for opionions from any database administartors of
> their perception of it.
>

I use explain plan all the time, specifically on complicated sql. It does the job at the end of the day. I normally keep a sql script around and just cut and paste in the sql for 'tuning' and the _at_ the script.

It is not a databae tuning tool rather a tool to tune the application, it is not usually wise to fine tune the DB to any great extent until the application has been tuned.

Most experienced people can look at a piece of code and identify an problems or potential problems but explain plan is an easy option.

To be honest I find tkprof used in conjunction with explain to be more useful. This helps to identify problems when the explain says everything is a-ok but then data access is the problem ie: an index is nor specific enough.

-- 
Mike Cox