That's probably it. It does return a large percentage of rows.

Thanks



-----Original Message-----
From: Birgitta Hauser [mailto:Hauser@xxxxxxxxxxxxxxx]
Sent: Wednesday, January 08, 2020 11:00 AM
To: 'Midrange Systems Technical Discussion' <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: RE: Why Table Scan?

A table scan is quite often performed if more than 15-20% of the rows of a table is returned (and there is no appropriate EVI).
<> and OR let expect that more than 15-20% of the rows are returned

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!"
"Train people well enough so they can leave, treat them well enough so they don't want to." (Richard Branson)


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