[AccessD] Very interesting quirk in table design...

Implying that a boolean field is a signed byte, and that could be why there 
are two bytes.  Form and code logic, bound or otherwise only require zero or 
not zero.  If I'm not mistaken, .Net is 0 and 1, or at least there were 
rumblings that this was going to be the case earlier in the .Net design 
process.  Maybe someone who knows can chime in.

I won't second guess Microsoft on why they went to a two byte field, I 
simply use a byte and occasionally, bits of the byte.  I see no reason for 
the datatype except that it displays a checkbox in the table, and my users 
don't see tables.  If Microsoft uses a signed byte for backward 
compatibility with VB and VBA, they could have used the first bit and made 
the numeric range -128 to 127 and kept it at a byte.  Signed and unsigned 
typically cover the same range of numbers execpt it starts at negative 1/2 
the value of the unsigned numeric.  Whatever their reasons, they seem 
illogical and inconsistent.

Hen


>From: "Charlotte Foust" <cfoust at infostatsystems.com>
>Reply-To: accessd at databaseadvisors.com
>To: <accessd at databaseadvisors.com>
>Subject: RE: [AccessD] Very interesting quirk in table design...
>Date: Wed, 14 May 2003 09:08:44 -0700
>
>:oP
>
>That would be -1 as opposed to 1.
>
>Charlotte Foust
>
>-----Original Message-----
>From: Gustav Brock [mailto:gustav at cactus.dk]
>Sent: Wednesday, May 14, 2003 7:49 AM
>To: accessd at databaseadvisors.com
>Subject: Re: [AccessD] Very interesting quirk in table design...
>
>
>Hi Charlotte
>
>Would that be for Not Yes and Not No?
>
>(sorry)
>
>/gustav
>
>
> > Is the additional byte for the sign?
>
> > Charlotte Foust
>
> > -----Original Message-----
> > From: Henry Simpson [mailto:hsimpson88 at hotmail.com]
> > Sent: Wednesday, May 14, 2003 6:30 AM
> > To: accessd at databaseadvisors.com
> > Subject: Re: [AccessD] Very interesting quirk in table design...
>
>
> > Curious that in Access 97, and I'll assume subsequent versions as
>well,
> > a yes/no field stores 2 bytes for each entry.  Using a numeric value
> > like a byte requires half the storage and gives you 8 states that
> > equate to 8 two state fields or 4 four state fields or whatever
> > other combination of 8 bits you devise, plus null.  I've never
> > understood why the yes/no field requires two bytes and use bytes for
> > boolean fields for the increased flexibility.
> > Form logic doesn't seem to require any change if you simply use one
>byte
> > field for each field requiring a boolean display.

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