Thanks Tom and Rod.
There are indeed several additional conditions on the real query which
prune the search space (I formulate a quick search box and filter on
Lat/Lon's within the box). Since my user interface limits the search to a 30
mile radius, there are at most 81 results (in New York city,
Thanks Tom and Rod.
There are indeed several additional conditions on the real query which
prune the search space (I formulate a quick search box and filter on
Lat/Lon's within the box). Since my user interface limits the search to
a 30
mile radius, there are at most 81 results (in New York
On Tue, 2005-04-12 at 23:08 -0700, Bill Lawrence wrote:
Thanks,
Unfortunately, I think that solution requires the distance calculation to be
executed twice for each record in the table. There are ~70K records in the
table. Is the postgres query optimizer smart enough to only perform the
Thanks,
Unfortunately, I think that solution requires the distance calculation to be
executed twice for each record in the table. There are ~70K records in the
table. Is the postgres query optimizer smart enough to only perform the
calculation once?
Bill
-Original Message-
From: Scott
Rod Taylor [EMAIL PROTECTED] writes:
You can force it with a subselect though:
SELECT * FROM (SELECT zipcode, zipdist($lat1d,$lon1d,lat,long)
as distance
from zipcodes) AS tab where distance = $dist;
The above will *not* stop zipdist from being run twice,
Why not just do:
SELECT zipcode, zipdist($lat1d,$lon1d,lat,long) as distance from
zipcodes where zipdist($lat1d,$lon1d,lat,long) = $dist;;
On Mon, 2005-04-11 at 20:25, Bill Lawrence wrote:
Boy I sure thought that would work... I received the following from postgres:
ERROR: Attribute
Thanks a bunch!
Looks pretty step-by-step at the site for the link you sent. I'll give it a
shot and see how it turns out.
Thanks again for all your help!
Bill
-Original Message-
From: PFC [mailto:[EMAIL PROTECTED]
Sent: Tuesday, April 12, 2005 1:03 AM
To: Bill Lawrence
Subject: Re:
try:
SELECT zipcode, zipdist($lat1d,$lon1d,lat,long) as distance from zipcodes
where distance = $dist;;
OR you could use a gist index with a geometric datatype to get it a lot
faster.
On Sat, 09 Apr 2005 03:43:39 +0200, Bill Lawrence [EMAIL PROTECTED]
wrote:
HI,
Im a newbie so please bear
HI,
Im a newbie so please bear with me. I have a function defined (got it
from one of your threads thanks Joe Conway) which calculates the distance between 2 zip code centeroids (in
lat,long). This thing works great. However, I want to sort my results by
distance without incurring the
