Re: quoting values magic

t == tgl(at)sss(dot)pgh(dot)pa(dot)us writes:

t> Brandon Metcalf <brandon(at)geronimoalloys(dot)com> writes:
t> > d == dalroi(at)solfertje(dot)student(dot)utwente(dot)nl writes:
t> > d> On May 26, 2009, at 6:37 PM, Brandon Metcalf wrote:
t> > d> > The issue here is that these reduce back to my original problem. For
t> > d> > example, if I use a CASE statement and I fall through to the ELSE,
t> > d> > then the SQL is attempting to insert a "''" in a NUMERIC field which
t> > d> > is not valid. That is, it's trying to do

t> > d> No it doesn't, read that statement again ;)

t> > Oops. Indeed, you are correct.

t> I think there is a problem though. If you have

t> case when '$length'='' then length else '$length' end

t> then what the parser is going to see is a CASE expression with a
t> variable (known to be NUMERIC) in one arm and an unknown-type literal
t> constant in the other arm. So it's going to decide that the literal
t> must be NUMERIC too, and that type coercion will fail if the literal
t> is really just ''.

t> Some experimentation suggests that you might get away with

t> case when '$length'='' then length else '$length'::text::numeric end

I think this is what I meant to say :) If $length contains a number,
then the resulting statement will be $length = '5.8', for example, and
this will fail for type NUMERIC.

--
Brandon