Why can't SQL SELECT's fire triggers

Oracle allows triggers to be fired when issuing SQL UPDATE, INSERT and DELETE, but not when doing a SELECT. I also see that this is not unique to Oracle as Sybase doesn't allow this.

What is the reasoning behind this. It seems logical to me that firing a trigger from a SELECT would be beneficial in many applications (e.g. access control).

Thanks

Earl Nall                                    Internet.ejn_at_ornl.gov
Martin Marietta Energy Systems, Inc.          Phone....615-574-8689 
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