Home -> Mailing Lists -> Oracle-L -> Re: Convert PLSQL update with forall

Re: Convert PLSQL update with forall

From: Andy Sayer <andysayer_at_gmail.com>
Date: Sun, 20 May 2018 22:14:41 +0100
Message-ID: <CACj1VR5S2gBXGTmVPU2DxFyqY1z9dmdLiY0Ff1+qwMKV=rejVw_at_mail.gmail.com> 








What sort of timings are you actually getting here and what do you need to
be getting?



Have you looked into where the time is really going? The performance impact
of 2 million (*2) context switches isn’t negligable but it’s not going to
turn something from way too slow to okay.



How long does the SQL in your for cursor take to execute and fetch 2
million results?


How long does one individual update take? Have you looked at the execution
plan of that?



Are you updating a table that you are querying inside that loop? (Causing
you to read undo you’ve just generated)



Hopefully that gets us looking in the right direction,
Andrew


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Received on Sun May 20 2018 - 23:14:41 CEST












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