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Home -> Community -> Usenet -> c.d.o.server -> Re: Is This the varchar2 ZLS Issue?
Tim Marshall wrote:
> Arto Viitanen wrote:
>
>> Tony Andrews wrote: >> >>> All correct - for Oracle. But note that the ANSI standard is that the >>> empty string is NOT null, and "where '' = ''" should always be TRUE. >>> This Oracle anomaly is a trap for those used to other DBMSs that honour >>> the ANSI standard on this point. >> >> I used to think this also. But honestly, where do you use value ''?
NULL.
That means: undefined, no information (which -freely interpreted- is
your "where information can be left out").
As Oracle treats '' (empty string) as NULL, you will not
win anything, using '' over NULL.
It will create misunderstanding, as Oracle's handling of
empty strings is an anomaly. But that is not your doing,
that's Oracles doing.
BTW: Why should a column never be NULL? A tuple may well be undefined at a certain time (e.g. number of children while status='SINGLE' - although some people... but that is entirely OT), but become meaningful at a later stadium.
-- Regards, Frank van Bortel Top-posting is one way to shut me up...Received on Mon Mar 20 2006 - 14:16:06 CST
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