Is the plan showing the operation CONCATENATION, or OR_EXPANSION as its
implementation of USE_CONCAT() ?
The thing I notice as significant (apart from the use_concat, of course) is
the
OPT_PARAM('_optimizer_null_accepting_semijoin' 'false')
which may be why the end up with a lateral view
"VW_LAT_EA451CA1"@"SEL$EA451CA1"
The other opt_params look as if they relate to the splitting of the 12.1
adaptive optimization parameter into two parts (and that could be part of
the problem, of course).
Have you tried cutting and pasting the Outline from the good plan into the
SQL to see if the hints are sufficient to reproduce the plan?
Can you run the query on a patched as well as unpatched version of the
software? If so running with the CBO trace (10053) enabled would allow you
to compare all the optimizer parameters and fix_controls that vary between
the two instances. Search for the heading PARAMETERS USED BY THE OPTIMIZER
Regards
Jonathan Lewis
On Fri, 27 Aug 2021 at 14:50, Chris Taylor <christopherdtaylor1994@xxxxxxxxx>
wrote:
For this it was "_no_or_expansion" to test getting rid of the USE_CONCAT.
(H/T to Noveljic for the help finding the param)
It didn't make any difference however.
Thanks,
Chris
On Fri, Aug 27, 2021 at 9:11 AM Noveljic Nenad <
nenad.noveljic@xxxxxxxxxxxx> wrote:
Hi,
Could you try
ALTER SESSION SET "_optimizer_cbqt_or_expansion"=off;
Best regards,
Nenad
____________________________________________________
Please consider the environment before printing this e-mail.
Bitte denken Sie an die Umwelt, bevor Sie dieses E-Mail drucken.
Important Notice
This message is intended only for the individual named. It may contain
confidential or privileged information. If you are not the named addressee
you should in particular not disseminate, distribute, modify or copy this
e-mail. Please notify the sender immediately by e-mail, if you have
received this message by mistake and delete it from your system.
Without prejudice to any contractual agreements between you and us which
shall prevail in any case, we take it as your authorization to correspond
with you by e-mail if you send us messages by e-mail. However, we reserve
the right not to execute orders and instructions transmitted by e-mail at
any time and without further explanation.
E-mail transmission may not be secure or error-free as information could
be intercepted, corrupted, lost, destroyed, arrive late or incomplete. Also
processing of incoming e-mails cannot be guaranteed. All liability of
Vontobel Holding Ltd. and any of its affiliates (hereinafter collectively
referred to as "Vontobel Group") for any damages resulting from e-mail use
is excluded. You are advised that urgent and time sensitive messages should
not be sent by e-mail and if verification is required please request a
printed version.
Please note that all e-mail communications to and from the Vontobel Group
are subject to electronic storage and review by Vontobel Group. Unless
stated to the contrary and without prejudice to any contractual agreements
between you and Vontobel Group which shall prevail in any case,
e-mail-communication is for informational purposes only and is not intended
as an offer or solicitation for the purchase or sale of any financial
instrument or as an official confirmation of any transaction.
The legal basis for the processing of your personal data is the
legitimate interest to develop a commercial relationship with you, as well
as your consent to forward you commercial communications. You can exercise,
at any time and under the terms established under current regulation, your
rights. If you prefer not to receive any further communications, please
contact your client relationship manager if you are a client of Vontobel
Group or notify the sender. Please note for an exact reference to the
affected group entity the corporate e-mail signature. For further
information about data privacy at Vontobel Group please consult
www.vontobel.com.
