On Mon, Oct 13, 2008 at 08:38:08AM +0200, H.Merijn Brand wrote:
> On Sun, 12 Oct 2008 21:25:12 +0100, Tim Bunce <[EMAIL PROTECTED]>
> wrote:
> > On Sun, Oct 12, 2008 at 02:55:51AM -0000, Greg Sabino Mullane wrote:
> > >
> > > > values are hashrefs of type information in the same form as that
> > > > provided to the various bind_param() methods
> > > ...
> > >
> > > > I'm not sure why the values of the keys are hash references unless
> > > > multiple values are to be stored. If multiple values per key are stored
> > > > what are they typically? I can only find one DBD which implements
> > > > ParamTypes (DBD::Pg) and unless I am mistaken it sets the values of the
> > > > keys to a scalar value - the type of the parameter.
> > >
> > > Yes, it's scalar values in DBD::Pg. If I recall correctly, it was done
> > > that
> > > way simply because it seemed better to return a simple name. To be 100%
> > > accurate it should probably return a hashref because that's what
> > > bind_param
> > > takes. In other words:
> > >
> > > $sth->bind_param('$1', 234, { pg_type => SQL_INTEGER });
> > > warn Dumper $sth->{ParamTypes};
> > >
> > > gives:
> > >
> > > $VAR1 = {
> > > '1' => 'integer'
> > > };
> > >
> > > When it should technically return:
> > >
> > > $VAR1 = {
> > > '1' => { pg_type => 'SQL_INTEGER' }
> > > };
> >
> > The intention is that this code:
> >
> > $ParamTypes = $sth1->{ParamTypes};
> > $ParamValues = $sth1->{ParamValues};
> >
> > $sth2->bind_param( $_, $ParamValues->{$_}, $ParamTypes->{$_} )
> > for keys %$ParamTypes;
> >
> > should make the values bound to $sth2, and the way they're treated by
> > the driver, be the same way as they were for $sth1.
> >
> > So { '1' => 'integer' } sure looks like a bug.
>
> But the underlying question was if it should return
>
> $VAR = { 1 => 1 };
>
> or
>
> $VAR = { 1 => { pg_type => 1 }};
>
> My DBD::Unify currently does the first. It returns numerical scalars,
> not hash-refs
I've no problem with ParamTypes returning the same value that was passed
to bind_param(), and bind_param() allows an integer:
$sth->bind_param( $i, $value, 1 );
is defined to be a shorthand for
$sth->bind_param( $i, $value, { TYPE => 1 } ); # and TYPE 1 is SQL_CHAR
It's important to remember, though, that that integer is the ANSI/ISO
defined TYPE value, not some driver-specific value.
Tim.
> > > However, bind_param currently saves the value to an internal form, without
> > > saving how it got there, which makes the key of that inner hash
> > > ('pg_type')
> > > difficult to show. Because the value, SQL_INTEGER, is really a constant,
> > > it's
> > > equally difficult to know to output 'SQL_INTEGER' - we'd really have to
> > > output
> > > the number it maps to.
> >
> > Yes. Outputting the _string_ "SQL_INTEGER" would be wrong as it wouldn't
> > work for the code above.
> >
> > > I can easily adjust ParamTypes in DBD::Pg to give a hashref, if that's
> > > what you end up doing for DBD::ODBC
>
> --
> H.Merijn Brand Amsterdam Perl Mongers http://amsterdam.pm.org/
> using & porting perl 5.6.2, 5.8.x, 5.10.x, 5.11.x on HP-UX 10.20, 11.00,
> 11.11, 11.23, and 11.31, SuSE 10.1, 10.2, and 10.3, AIX 5.2, and Cygwin.
> http://mirrors.develooper.com/hpux/ http://www.test-smoke.org/
> http://qa.perl.org http://www.goldmark.org/jeff/stupid-disclaimers/
