SQL Indexes

I have in my library of data files some SQL indexes on some physical file that are named using the first 5 characters of the Physical file and then a sequential number starting with 00001. For example ABCDE00001, ABCDE00002 where the Physical file name is ABCDEFGHI. Does anyone know where or how or why these Indexes are created. Also every once in a while a Physical file is created instead of an Index such as ABCDE00010.*file.pf-dta as opposed to ABCDE00009.*file.lf. I cannot determine how these files are being created and would like to remove them but only if they are of some use. Any information would be appreciated. Thanks.

(PS. I cc'd everyone I thought should be aware of this but if I've forgotten anyone then my apologies and could you please forward this to anyone you feel should be informed.)

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Don Wereschuk
ISD - Programmer/Analyst
Simcoe Parts Service Inc.
Phone: 705-435-7814 Ex: 5325
Fax: 705-435-5029
mailto:dwereschuk@xxxxxxxxxxxxxxx
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If you can't describe what you are doing as a process, you don't know what you're doing.
W. Edwards Deming