Re: Modyifying a column's datatype

Hi,

If your data is good for the new type as it is, one way to alter name and type
is by editing the dumb -c file's CREATE TABLE statement. This will also
preserve your column order, if it really matters.

BR,

Aarni

On Thursday 04 September 2003 01:55, you wrote:
> --- Ron Johnson <ron(dot)l(dot)johnson(at)cox(dot)net> wrote:
> > On Wed, 2003-09-03 at 14:56, Louise Cofield wrote:
> > > Greetings –
> > >
> > >
> > >
> > > It looks to me as if there is no way to alter the
> >
> > datatype of a table
> >
> > > column, as in from timestamp to varchar. Am I
> >
> > right? (I will cry if
> >
> > > I’m right.) L.
> > >
> > > It appears that I must drop and then re-create the
> >
> > table structure,
> >
> > > with my new column datatype, in order to keep the
> >
> > columns in the
> >
> > > current order – true?
> >
> > There are references to this all throughout the
> > archives.
> >
> > begin;
> > alter table foo add column bar varchar;
> > update foo set bar = cast(sniffle as varchar);
> > alter table foo drop column sniffle;
> > alter table foo rename column bar to sniffle;
> > commit;
>
> I don't believe that this will preserve the column
> order, which the OP wanted. The only alternative that
> I know of is to hack the system tables, but that is
> definitely risky.
>
> Column order is not supposed to matter, but it is
> amazing how many (brain dead) applications there are
> that rely on it.
>
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