Re: NULLs: theoretical problems?


"sinister" <sinister@xxxxxxxxxxxxxx> wrote in message
news:wa-dnYfs8-TuAyTbnZ2dnUVZ_tSknZ2d@xxxxxxxxxxxxxx
Many discussions point out one deficiency of NULLs: that they collapse
multiple, distinct concepts into one ("no value possible," "value
missing,"
"value not available at this time", etc).

What are the other theoretical problems? My impression from skimming some
threads in this ng is that some anomalies might occur, maybe having to do
with NULLs and joins, or NULLs and keys composed of more than one field,
but
I'm not sure.


"Nothin' ain't worth nothin', but it's free."
--Kris Kristofferson --


.

Relevant Pages

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