| From: | Peter Geoghegan <pg(at)heroku(dot)com> |
|---|---|
| To: | Stephen Frost <sfrost(at)snowman(dot)net> |
| Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Robert Haas <robertmhaas(at)gmail(dot)com>, Michael Paquier <michael(dot)paquier(at)gmail(dot)com>, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com>, Abhijit Menon-Sen <ams(at)2ndquadrant(dot)com>, PostgreSQL mailing lists <pgsql-hackers(at)postgresql(dot)org>, Josh Berkus <josh(at)agliodbs(dot)com>, Ian Barwick <ian(at)2ndquadrant(dot)com>, Andres Freund <andres(at)2ndquadrant(dot)com>, Greg Stark <stark(at)mit(dot)edu>, Jim Nasby <jim(at)nasby(dot)net>, Albe Laurenz <laurenz(dot)albe(at)wien(dot)gv(dot)at> |
| Subject: | Re: Doing better at HINTing an appropriate column within errorMissingColumn() |
| Date: | 2014-12-21 00:30:14 |
| Message-ID: | CAM3SWZT+sTAqR9DqKw+pr2Sfuhu_8w-z8zGpbm=iytdOVo4gFA@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Sat, Dec 20, 2014 at 3:17 PM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:
> Attached patch implements this scheme.
I had another thought: "NAMEDATALEN + 1" is a better representation of
"infinity" for matching purposes than INT_MAX. I probably should have
made that change, too. It would then not have been necessary to
"#include <limits.h>". I think that this is a useful
belt-and-suspenders precaution against integer overflow. It almost
certainly won't matter, since it's very unlikely that the best match
within an RTE will end up being a dropped column, but we might as well
do it that way (Levenshtein distance is costed in multiples of code
point changes, but the maximum density is 1 byte per codepoint).
--
Peter Geoghegan
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Alvaro Herrera | 2014-12-21 01:54:16 | Re: PATCH: decreasing memory needlessly consumed by array_agg |
| Previous Message | Peter Geoghegan | 2014-12-20 23:17:59 | Re: Doing better at HINTing an appropriate column within errorMissingColumn() |