Index Advisor Recommending an EVI That Already Exists -- MIDRANGE-L

Subject: Index Advisor Recommending an EVI That Already Exists
From: Gord Hutchinson <gordm1@xxxxxxxxxxxxxxx>
Date: Fri, 6 Sep 2019 11:13:24 -0400
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The index advisor is currently recommending an EVI (over 300,000 times) for
an EVI that already exists.

The only difference (I can see) in the generated SQL and the SQL for the
index already in place is the number of distinct values. The generated SQL
always defaults to 65537 distinct values and it specifies an ascending
key. The existing EVI only specified 2500 distinct values (there are
actually only 1987) and the ASC keyword is not specified.

Any suggestions why this would happen?

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