From the stand point of the query engine, there's a difference between
a DDS logical and an SQL index. Primarily, the SQL index has a larger
page size. But I _think_ there's more statistics kept also.

So yes, the SQE may ask for an index even if a logical with the same key exists.

To give the SQE its index and eliminate duplication of the access path, either:
--delete the logical and create the index with the name of the logical
(done correctly, file ID is the same and no programs need to be
--delete the logical, create the index, recreate the logical. The
logical will then share the access path from the index.

As far as answering if having the index is worth it, depends. How
many days did it take to get to the index recommended 61 times?

If you don't know, consider clearing the indexes advised. Then
checking again after a week or two.


On Wed, Sep 2, 2009 at 1:42 PM, <JDHorn@xxxxxxxxxxxxxx> wrote:
  While reviewing the sql index advisor, it seems to be telling me to create
  a 64KB Binary Radix index over our customer file (which has only 31,000
  records in it) which currently has a ddl described logical file for it
  with exactly the same key (customer#).

  times advised-61, est idx creation time 6:59, most expensive estimate 419,
  average of queery estimates 108, records in table when advised 31374.

  does this seem odd?   is it worth it?

  it is doing the same thing over some other (vastly larger) files also.

  Jim Horn
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