Re: Rule Based Optimizer

Assuming we are talking about "Index Unique Scan' and 'Index Range Scan', these are described in the Concepts manual - for 9iR2 in Chapter 10, under Indexes, in the section "How Indexes Are Searched"

In the docco, the difference is basically:

Unique scan: find a matching key and return the rowid Range scan: for each key between lower and upper bound, return rowid

For the exact details, see

http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96524/c11schem.htm#3239

hth/FGB Received on Wed Mar 02 2005 - 21:21:23 CET