Re: Help on execution plan

Mark,

thanks for your feedback. I was thinking about the columns beeing part of an index already. The funny thing about this, is that the index which *is* used when I remove the two columns is not the index that is beeing reported by EXPLAIN PLAN. The index beeing use is the one over (id, product_no) although there is one over (id, name, product_no, ca_code). That's basically the reason why I wasn't considering the index read.

And yes, I have tried using hints, but any of the indexes I specify make it or doesn't change too much.

I am aware of the fact that an index scan *can* be more expensive then a FTS but taking into account that the table has 4.5 million rows (in the test environment, production has about 9 million rows) I would expect an index range scan still beeing less expensive....

Thomas

mcstock schrieb:

> the columns that remain in the select list likely are being read from the
> index -- is there any other type table access for 'big_table' in the
> execution plan replacing the FTS?
> does anything else in the plan change?
> have you looked into hints to force the index range scan (which may not be
> so cheap with the additional columns included -- the optimizer may be making
> a correct choice in this case)
>
Received on Thu Nov 06 2003 - 07:19:24 CST