Is this really the case. I used to think this was the case, but somewhere
along the way to studying for the OCP exams, I read and accepted that NO
hints were available if you were using the RULE based optimizer. I guess
I
need to fire up my test instance later today, and figure this out.
Can you give me starting values to try in the optimizer parameters?
Ron
-Original Message-
Sent: Monday, August 11, 2003 3:44 PM
To: Multiple recipients of list ORACLE-L
to 8.1.7
Yes it does. 8i has parameters optimizer_index_cost_adj and
optimizer_index_caching, which don't exist in
The old and new versions were both set to CHOOSE. Both are analyzed.
Are you saying 8.1.7 handles this differently?
Thanks!
Ron
-Original Message-
Sent: Monday, August 11, 2003 3:04 PM
To: Multiple recipients of list ORACLE-L
to 8.1.7
RBO, CBO, the old story. If you plan to continue
Yes it does. 8i has parameters optimizer_index_cost_adj and
optimizer_index_caching, which don't exist in 7.3. And these parameters'
default values aren't optimal.
Also, when testing your app, be sure that you're comparing oranges with
oranges, e.g. if your app uses bind variables but your
RBO, CBO, the old story. If you plan to continue using 8.1.7 for a
While, then set the parameter OPTIMIZER_MODE to RULE. Your performance
will be normal again and programmers will be able to override the parameter
By specifying any hint except /*+ RULE */. Before switching to CBO, please
read the
then set the parameter OPTIMIZER_MODE to RULE. Your performance
will be normal again and programmers will be able to override the
parameter
By specifying any hint except /*+ RULE */.
Is this really the case. I used to think this was the case, but somewhere
along the way to studying for the OCP
Differently from what? Differently from V7? But of course! The optimizer
is very, very different. It will frequently give different results.
--
Mladen Gogala
Oracle DBA
-Original Message-
Smith, Ron L.
Sent: Monday, August 11, 2003 4:24 PM
To: Multiple recipients of list ORACLE-L
L.
Sent: 11 August 2003 22:04
To: Multiple recipients of list ORACLE-L
Subject: RE: Poor performance after moving Extempore database
from 7.3.4 to 8.1.7
Can you give me starting values to try in the optimizer
parameters? Ron
-Original Message-
Sent: Monday, August 11, 2003 3
