Re: oracle can ignore hints

  • From: "Jonathan Lewis" <jonathan@xxxxxxxxxxxxxxxxxx>
  • To: <oracle-l@xxxxxxxxxxxxx>
  • Date: Thu, 4 Mar 2004 21:39:37 -0000


The intent is that they should be absolute directives;
but there are conditions that put hints out of context,
which means they become irrelevant.

If it can happen at all, it can be hinted.


Jonathan Lewis

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----- Original Message ----- 
From: "April Wells" <AWells@xxxxxxxxxx>
To: <oracle-l@xxxxxxxxxxxxx>
Sent: Thursday, March 04, 2004 7:44 PM
Subject: RE: oracle can ignore hints

: Yep, they are 'friendly suggestions' that the CBO can simply choose to
: ignore if it thinks it knows better than you.
: We have one query that we have hinted, we have computed statistics, we
: built histograms, we have jumped through hoops... the only way to force it
: to use an index is to Never analyze that index and to hope, then, that the
: CBO makes the right assumptions.

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