Re: Details needed on using the parallel query option

>
> Brian M. Biggs wrote:
> > The way I understand the parallel query option, it can be invoked
> > primarily in 2 ways:
> > (1) by ALTERing a table and indicating that it is a parallel table
> > (2) putting hints in your SQL code to indicate that a certain SQL
> > statement should be executed in parallel.-SNIP-
> > Is there a way to tell Oracle "only execute this query in parallel if
> > you have more than 1 processor"? Or, rather than being that specific,
> > is there a better way to control when your application does and does not
> > use the parallel query option? What is the best way to manage this
> > feature?

I thought of a second way to do this. The two init.ora parameters "parallel_default_max_scans" and "parallel_default_scansize" are for the servers to use when you don't specify the degree in a hit clause. So modify your hint statments from /*+ full(table_name) parallel(table_name,4) */ to /*+ full(table_name) parallel(table_name) */. Now customize your init.ora parameters on each machine for the number of processors available. I haven't done it this way myself but with a little testing you should be able to get some kind understanding of what works right.

-- 
                       \\|//
                       (0-0)
           +-----oOO----(_)-----------+
           | Brian P. Mac Lean        |
           | Database Analyst         |
           | brian.maclean_at_teldta.com |
           | http://www.teldta.com    |
           +-------------------oOO----+
                      |__|__|
                       || ||
                      ooO Ooo