Re: Boolean datatype in Oracle?
Date: Tue, 21 Nov 2000 14:55:02 -0500
Message-ID: <8veju6$111$1_at_bob.news.rcn.net>
Three cases are preferable, IMO:
NULL
YES
NO
They each have a different meaning. Null means that a choice has not yet
been made, which is different than YES or NO, and is also meaningful data.
Note that a CHECK constraint will ignore Nulls, which is desireable in this
case.
Note also, that in user interface design:
an unchecked check box is not necessarily the same as a check box that has
been checked and then unchecked. Usually
Unfortunately, 1 and 3 appear the same to the user, which is why radio
buttons (mutually exclusive, mandatory once clicked controls) are preferable
for Boolean fields:
neither button clicked = Null
This eliminates any ambiguity as well as uncerainty on the users' part.
"Frank van Bortel" <fbortel_at_home.nl> wrote in message
news:3A240618.2D21C13C_at_home.nl...
Yes button = Yes
No button = No
> Or, if you happen to have a non-mandatory column:
> value)
>
> Alan wrote:
>
> > Just use a CHAR(1) and use a CHECK constraint to limit the entries to Y
and
> > N or 1 and 2, or whatever.
> >
> > "Robert Martin" <rwmartin_at_sisconet.com> wrote in message
> > news:8vc26606o7_at_enews3.newsguy.com...
> > > Well, I am converting an SQL Server 7.0 database to an Oracle 8i
database
> > > and just want to convert things as best as I can.
> > >
> > > -------------------------------------------
> > > Robert Martin (rwmartin_at_sisconet.com)
> > > Design Engineer
> > > SISCO Inc,
> > > 6605 19 1/2 Mile Road
> > > Sterling Heights, MI 48314-1408
> > > Phone : 810-254-0020 (ext 125)
> > > Fax : 810-254-0053
> > > "Frank van Bortel" <fbortel_at_home.nl> wrote in message
> > > news:3A22C203.91062EB1_at_home.nl...
> > > > IMHO you don't need one - just compare a column value with a
literal;
> > > > the outcome is boolean:
> > > > WHERE <column_name> = <literal>
> > > >
> > > > Robert Martin wrote:
> > > >
> > > > > What is the best way in an Oracle database to represent a Boolean
value
for
> > > > > a column in a table? I see there is no simple Boolean datatype
(which
I
find
> > > > > to be pretty lame IMO). Thanks in advance.
> > > > >
> > > > > -------------------------------------------
> > > > > Robert Martin (rwmartin_at_sisconet.com)
> > > > > Design Engineer
> > > > > SISCO Inc,
> > > > > 6605 19 1/2 Mile Road
> > > > > Sterling Heights, MI 48314-1408
> > > > > Phone : 810-254-0020 (ext 125)
> > > > > Fax : 810-254-0053
> > > >
> > > > --
> > > > Gtrz,
> > > >
> > > > Frank van Bortel
> > > >
> > > >
> > >
> > >
>
> --
> Gtrz,
>
> Frank van Bortel
>
>
Received on Tue Nov 21 2000 - 20:55:02 CET