Re: Unique indices and nulls

>>>>> "Josh" == Josh Berkus <josh@agliodbs.com> writes:

    Josh> All DBAs are guilty of, to a lesser or greater degree, using
    Josh> NULL to represent "None", even though NULL actually means
    Josh> "unknown" according to the SQL spec.  The rest of the SQL
    Josh> spec is designed to support NULLs as "unknown", so this can
    Josh> lead to problems in application.  Like yours.

This is a good point, and since I know the range of values which can
go into those columns, it is easy to pick something to use as
representing "none."

roland
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Roland B. Roberts, PhD                             RL Enterprises
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