Excellent suggestion.
Now I haven’t read the full thread yet, but I immediately have 3 questions
(that may be in there when I dig):
1) Parallel query?
2) RAC?
3) Force parallel query local?
A wide variety of hilarity can be seen in RAC parallel query NOT forced local
on most of 12.1 (and some of 12.2). Hmm actually it can happen forced local on
12.1, but I think that at least was patched for 12.2. A symptom of the BUG I
reference would be either parallel forced to serial (having given up trying to
get identical FULL HASH on child plans) or a long parse time finally getting
the matching children to feed to the coordinator.
That may be a zebra whilst you’re looking for a sick horse, and there are a lot
of fine responses from the few I’ve read in the thread, so take my comment with
a salt shaker.
mwf
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Sayan Malakshinov
Sent: Friday, November 01, 2019 1:23 AM
To: breitliw@xxxxxxxxxxxxx
Cc: ORACLE-L; JBECKSTROM@xxxxxxxxx; tanel@xxxxxxxxxxxxxx
Subject: Re: Force specific plan to be used
Hi all,
Since OP is talking about adaptive plans with multiple child cursors, I would
check FULL_PLAN_HASH_VALUE and PLAN_HASH_2.