Telephone index

[John Pearce]

My users have asked that I provide an index on the telephone number field 
in a dataset.  It's presently a character field to allow notes like 
"non-pub" or "disconnected" to explain why there's no phone number.  The 
environment is HP ImageSQL and PH 8.39.  My concern is the performance 
issues created by 46,500 blank phone numbers that would be in one 
chain.  There are fewer than 1000 telephone numbers that contain notes like 
"non-pub" so that is not a concern (at least not yet).

To avoid the lengthy chain of blank telephone numbers I'm thinking about 
adding code to the PREUPDATE procedure to replace a blank phone number with 
a string consisting of a $ plus the unique six digit ID number for the 
record.  Then have a POSTFIND procedure that checks for the leading $ and 
blanks out the field for display.  Does anyone see any problems with this 
approach?

Thanks,
John
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John Pearce  <jpearce@rmi.net>	| Bethesda Management Company
Speaking for only myself		| Colorado Springs, CO  USA