Re: select * from mytable where myfield=null;

Is it good practice to use NULL values for foreign key
fields?

Thanks,
Noel
--- Hoanui Morangie <hoanui(at)excite(dot)com> wrote:
>
> I need NULL value, some of these columns are foreign
> keys. And using dummy values is not good practice
> anyway.
>
> Hoanui
>
>
>
> --- On Tue 05/14, Marin Dimitrov wrote:
> >
> >
> >
> >
> >
> >
> >
> >
> > style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px;
> MARGIN-LEFT: 5px;
> > BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT:
> 0px">
> > ----- Original Message -----
> > style="BACKGROUND: #e4e4e4; FONT: 10pt arial;
> font-color:
> > black">From:
> > Hoanui
> > Morangie
> >
> >
> > Hi, I understand that this behavior is a
> standard but agree
> > with
> > Bruno that it's nonsense. I have trouble with it
> in my own application.
> > I use
> > sql command like "select * from A where A.a=?
> and A.b=? and A.c=? and
> > A.d=?
> > and A.e=?". There are five parameters in my
> query and each of them can
> > be
> > null! I can not create SQL command string for
> all possible combinations
> > of
> > null values so I have to build the query
> dynamically. Why then use
> > prepared
> > statement? I doubt that anybody ever needed
> x=null in SQL
> > command but
> > it seems that my example is very common. There
> SHOULD be some workaround
> > for
> > that. But I agree that this is not topic for
> this list.
> >
> >
> >
> > don't use NULLs - introduce a dummy value
> > that bears the
> > semantic of NULL so u can use "= XXX" instead of "
> is
> > NULL"
> >
> > hth,
> >
> > Marin
> >
> > ----"...what you
> > brought
> > from your past, is of no use in your present. When
> you must choose a
> > new
> > path, do not bring old experiences with you. Those
> who strike out
> > afresh,
> > but who attempt to retain a little of the old
> life, end up torn apart
> > by
> > their own memories. "
> >
> >
>
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