On Tue, May 23, 2006 at 07:13:08PM +0200, Yonatan Ben-Nes wrote:
> UPDATE treecategory SET box =
> '('||"nleft"||','||"nright"||'),('||"nleft"||','||"nright"||')';
> ERROR: column "box" is of type box but expression is of type text
> HINT: You will need to rewrite or cast the expression.
>
> And if I try to cast type text to box I get:
> ERROR: cannot cast type text to box
Try this:
UPDATE treecategory SET box = box(point(nleft, nright), point(nleft, nright));
A hackish way to convert types where no cast exists is to use the
source and destination types' I/O functions:
UPDATE treecategory SET box = box_in(textout( <text expression> ));
You could create a function that implicitly does the above conversion:
CREATE FUNCTION box(text) RETURNS box AS $$
BEGIN
RETURN $1;
END;
$$ LANGUAGE plpgsql IMMUTABLE STRICT;
UPDATE treecategory SET box = box( <text expression> );
If you need to perform such conversions regularly then you could
use CREATE CAST to create a cast between the types.
--
Michael Fuhr
