1. What happens if you add an Order By to your SELECT statement with the range?
2. What happens if you additionally create a derived index over the relative record no?
Mit freundlichen Grüßen / Best regards
Birgitta Hauser
"Shoot for the moon, even if you miss, you'll land among the stars." (Les Brown)
"If you think education is expensive, try ignorance." (Derek Bok)
"What is worse than training your staff and losing them? Not training them and keeping them!"
-----Ursprüngliche Nachricht-----
Von: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] Im Auftrag von Charles Wilt
Gesendet: Thursday, 28.7 2016 16:46
An: Midrange Systems Technical Discussion
Betreff: RRN in SQL and Full table scan...
Back in May there was a thread where Birgitta mentioned that "Sometime in release 6.1? / 7.1?. the table scan for RRN was changed to an values list access, i.e. the list containing RRNs is searched first and with the result an access to the record performed.
"
A test with WHERE RRN(A) = 750000
Showed the "VALUES LIST" in Visual Explain.
However, today I tried
WHERE RRN(A) between 750000 and 750010
And I see a full table scan in VE.
This however, shows a values list..
WHERE RRN(A) IN (750000, 750001, 750002, 750003, 750004, 750005, 750006, 750007, 750008, 750009, 750010)
I'm running 7.1 TR 9.
Charles
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