Slavica Stefic wrote:
> is null = null true or also null?
A null value represents either the absence of data or
an unknown value. A null value is not
the same as a zero or a blank.
Thus two tuples with null values are never the same and can not
be joined.
> it appears that two null records are not equal if they are both null.
> First question: is this correct? is this SQL conformant?
yes
> 2: if I change the sources for the operator to compare nulls as
> they where values
> will it have too many side effects?
Don't do that. You will get a desaster ;-)
Herbie
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Herbert Liechti E-Mail: Herbert.Liechti@thinx.ch
ThinX networked business services Stahlrain 10, CH-5200 Brugg
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