Re: optimizer rewriting query

Hi,

Oracle breaks the query into a parse tree in order to make it understandable and optimizable to it - there is no point to put the optimized query back to SQL text format again, at least from Oracle database engine point of view, execution uses the parsed & compiled structures anyway.

There is an unparse operation in Oracle, for example for distributed and parallel queries Oracle generates the SQL statements to be sent to remote node or given to PX slaves. However this unparse is available only as internal kernel function as I understand so no help for us from there...

The best we can do is guess based on access/filter/event 10060 predicates and possibly LIO traces for seeing in which order segments/blocks get accessed...

Tanel.

• Original Message ----- From: "rjamya" <rjamya_at_gmail.com> To: <amit.poddar_at_yale.edu> Cc: "Karen Morton" <Karen.Morton_at_hotsos.com>; <oracle-l_at_freelists.org> Sent: Sunday, March 13, 2005 3:00 AM Subject: Re: optimizer rewriting query

> you cannot see the re-written query, but only thing you can see is the
> access plan. As Karen mentioned, you can access those views to see
> in-memory plans.
>
> Raj

--
http://www.freelists.org/webpage/oracle-l