[Mono-list] MySQL and NULL values

[Derek Hamilton]

One more thing about this...the same thing happened whether running it with
csc or msc.

Derek

----- Original Message -----
From: "Reggie Burnett" <rykr@bellsouth.net>
To: "'Derek Hamilton'" <derek@capweb.com>; <mono-list@ximian.com>
Sent: Friday, February 07, 2003 7:15 PM
Subject: RE: [Mono-list] MySQL and NULL values


> Derek
>
> I am not sure what is going on here.  I am using the driver in a site of
> mine and certainly have nulls in that database.  I'll take a look and
> post what I find.
>
> Reggie
>
> > -----Original Message-----
> > From: mono-list-admin@lists.ximian.com [mailto:mono-list-
> > admin@lists.ximian.com] On Behalf Of Derek Hamilton
> > Sent: Friday, February 07, 2003 6:05 PM
> > To: mono-list@ximian.com
> > Subject: Re: [Mono-list] MySQL and NULL values
> >
> > Sorry to reply to my own post so quickly.  I'm not sure exactly who to
> > send
> > this to (never worked with open source before) but I found the line of
> > code
> > that is causing NULL values to fail in the BtyeFX code.
> >
> > In the datareader.cs page if this:
> >
> > public bool IsDBNull(int i)
> > {
> >      return DBNull.Value == GetValue(i);
> > }
> >
> > is changed to
> >
> > public bool IsDBNull(int i)
> > {
> >      return GetValue(i) == null;
> > }
> >
> > then the IsDBNull will actually catch NULL values where as before it
> would
> > not (at least in my case).  I'm not really sure why the System.DBNull
> > wouldn't catch this.
> >
> > Thanks,
> > Derek Hamilton
> >
> > ----- Original Message -----
> > From: "Derek Hamilton" <derek@capweb.com>
> > To: <mono-list@ximian.com>
> > Sent: Friday, February 07, 2003 3:35 PM
> > Subject: [Mono-list] MySQL and NULL values
> >
> >
> > > Hello all,
> > >
> > > I am using the ByteFX library for MySQL db access and am
> experiencing
> > > trouble with NULL.  I am wondering if this is a MySQL problem (I
> > remember
> > > something about null handling being a problem in that past) or a
> > BtyeFX/mono
> > > problem.
> > >
> > > Specifically, if I create a MySQLDataReader and Read() through the
> > results
> > > where the results all have values it works fine.  If I try reading
> > through
> > a
> > > result set with any kind of NULL I get a "Object reference not set
> to an
> > > instance of an object."
> > >
> > > If I change all the nulls in my db to be an empty string the problem
> > doesn't
> > > occur.  I'm just not sure how feasible that is.
> > >
> > > Any advice?
> > >
> > > Thanks,
> > > Derek Hamilton
> > >
> > > _______________________________________________
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> > >
> >
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>
>