I also saw that in the PT&T training manual that I have, but it didn't make a difference when I tried. Thanks for the suggestion Axton, I will let you know how it goes.
On 5/4/06, McKenzie, James J C-E LCMC HQISEC/L3 <[EMAIL PROTECTED]> wrote:
** Axton: That was directly from the PT&T class and was enforced by some basic ORACLE training that I received. Here is gist of the training: If the query can be closed end (i.e. equals) then the optimizer will look to see if the index can be used. This happens at the point where about eight percent or less of the index entries are pulled back. If the query is not closed end (i.e not equals) then the optimizer will do a full table scan. So the key here is what is and is not closed end. If the entry has an equals sign in it like the following: 'Status' <= "Pending" the optimizer SHOULD look at the index and see approximately how many entries would be pulled back. 'Status' < "Resolved" SHOULD result in a full table scan. The key here is that the data in the field must be highly variable OR the data is bunched around a single value. In this case, over 280,000 of about 300,000 have a single value with the remaining 20,000 (less than 8%) are scattered around the remaining values. So, if the training I received is correct, using the <= value should result in an index scan IF you do not use the value with 280,000 entries, which is the case here. I don't have a form with 1,000 let alone 100,000 entries. Does anyone want to confirm/deny that this is the case? James McKenzie L-3 GSI
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