Re: Re: pg_stat_statements normalisation without invasive changes to the parser (was: Next steps on pg_stat_statements normalisation)

On 21 February 2012 01:48, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> you're proposing to move the error pointer to the "42", and that does
> not seem like an improvement, especially not if it only happens when the
> cast subject is a simple constant rather than an expression.

I'm not actually proposing that though. What I'm proposing, quite
simply, is that the Const location actually be correct in all
circumstances. Now, I can understand why the Coercion node for this
query would have its current location starting from the "CAST" part in
your second example or would happen to be the same as the Constant in
your first, and I'm not questioning that. I'm questioning why the
Const node's location need to *always* be the same as that of the
Coercion node when pg_stat_statements walks the tree, since I'd have
imagined that Postgres has no business blaming the error that you've
shown on the Const node.

--
Peter Geoghegan       http://www.2ndQuadrant.com/
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