Horton

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

Daniel Farina <daniel@heroku.com>

View thread
From: Daniel Farina <daniel@heroku.com>
To: Peter Geoghegan <peter@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Robert Haas <robertmhaas@gmail.com>, PG Hackers <pgsql-hackers@postgresql.org>
Date: 2012-02-29T09:05:01Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.

  2. Extend the parser location infrastructure to include a location field in

  3. Teach eval_const_expressions() to simplify an ArrayCoerceExpr to a constant

Attachments

On Mon, Feb 27, 2012 at 4:26 AM, Peter Geoghegan <peter@2ndquadrant.com> wrote:
> This does not appear to have any user-visible effect on caret position
> for all variations in coercion syntax, while giving me everything that
> I need. I had assumed that we were relying on things being this way,
> but apparently this is not the case. The system is correctly blaming
> the coercion token when it finds the coercion is at fault, and the
> const token when it finds the Const node at fault, just as it did
> before. So this looks like a case of removing what amounts to dead
> code.

To shed some light on that hypothesis, attached is a patch whereby I
use 'semantic analysis by compiler error' to show the extent of the
reach of the changes by renaming (codebase-wide) the Const node's
location symbol.  The scope whereby the error token will change
position is small and amenable to analysis.  I don't see a problem,
nor wide-reaching consequences.  As Peter says: probably dead code.
Note that the cancellation of the error position happens very soon,
after an invocation of stringTypeDatum (on two sides of a branch).
Pre and post-patch is puts the carat at the beginning of the constant
string, even in event there is a failure to parse it properly to the
destined type.

-- 
fdr