Thread: Need Help to implement Proximity search feature

Need Help to implement Proximity search feature

From
itishree sukla
Date:
Deal all, 

In my project, there is a requirement to implement proximity search feature. We are running a mobile app, for which proximity search is require. Can any one guide me how i can achieve this using postgis, or is there any other way i can achieve this.

We are using postgresql 9.2. 

Thanks in advance .

Regards, 
Itishree

Re: Need Help to implement Proximity search feature

From
Oleg Bartunov
Date:
check knn search, http://www.sai.msu.su/~megera/postgres/talks/pgcon-2010-1.pdf

On Wed, Jan 15, 2014 at 8:04 PM, itishree sukla
<itishree.sukla@gmail.com> wrote:
> Deal all,
>
> In my project, there is a requirement to implement proximity search feature.
> We are running a mobile app, for which proximity search is require. Can any
> one guide me how i can achieve this using postgis, or is there any other way
> i can achieve this.
>
> We are using postgresql 9.2.
>
> Thanks in advance .
>
> Regards,
> Itishree


Re: Need Help to implement Proximity search feature

From
itishree sukla
Date:
Thanks for your reply, i am totally new to Postgis.

we have Database, but not ready for Geocode use.  what i understood from different blog, we should have latitude and longitude either based on addresses, or postal code we have. However if I will get the lat and long, need to calculate earth distance to give  location based on user location. Formula i got, is calculating shortest distance, which always not true practically. Please address my concern, how i will get rid of these issues.

Regards,
Itishree


On Wed, Jan 15, 2014 at 11:28 PM, Oleg Bartunov <obartunov@gmail.com> wrote:
check knn search, http://www.sai.msu.su/~megera/postgres/talks/pgcon-2010-1.pdf

On Wed, Jan 15, 2014 at 8:04 PM, itishree sukla
<itishree.sukla@gmail.com> wrote:
> Deal all,
>
> In my project, there is a requirement to implement proximity search feature.
> We are running a mobile app, for which proximity search is require. Can any
> one guide me how i can achieve this using postgis, or is there any other way
> i can achieve this.
>
> We are using postgresql 9.2.
>
> Thanks in advance .
>
> Regards,
> Itishree

Re: Need Help to implement Proximity search feature

From
Gavin Flower
Date:
Please see the comment at the bottom of this post.

On 16/01/14 22:52, itishree sukla wrote:
Thanks for your reply, i am totally new to Postgis.
At least you've got into it, I keep meaning do do so myself.


we have Database, but not ready for Geocode use.  what i understood from different blog, we should have latitude and longitude either based on addresses, or postal code we have. However if I will get the lat and long, need to calculate earth distance to give  location based on user location. Formula i got, is calculating shortest distance, which always not true practically. Please address my concern, how i will get rid of these issues.

Regards,
Itishree


On Wed, Jan 15, 2014 at 11:28 PM, Oleg Bartunov <obartunov@gmail.com> wrote:
check knn search, http://www.sai.msu.su/~megera/postgres/talks/pgcon-2010-1.pdf

On Wed, Jan 15, 2014 at 8:04 PM, itishree sukla
<itishree.sukla@gmail.com> wrote:
> Deal all,
>
> In my project, there is a requirement to implement proximity search feature.
> We are running a mobile app, for which proximity search is require. Can any
> one guide me how i can achieve this using postgis, or is there any other way
> i can achieve this.
>
> We are using postgresql 9.2.
>
> Thanks in advance .
>
> Regards,
> Itishree

Pleas bottom post like I am here, it is the norm for these mailing lists.  Some comments interspersed are also okay.

It makes it easier for people to see the context of what you are saying.

Thanks,
Gavin

Re: Need Help to implement Proximity search feature

From
John R Pierce
Date:
On 1/16/2014 1:52 AM, itishree sukla wrote:
> we have Database, but not ready for Geocode use.  what i understood
> from different blog, we should have latitude and longitude either
> based on addresses, or postal code we have. However if I will get the
> lat and long, need to calculate earth distance to give  location based
> on user location. Formula i got, is calculating shortest distance,
> which always not true practically. Please address my concern, how i
> will get rid of these issues.

for determining closest proximity, you probably don't need accurate
spherical earth distance, simple cartesian distance is good enough as
you're only interested in relative values.  for this, you can use the
built in postgresql POINT data type, and the <->  distance operator.



--
john r pierce                                      37N 122W
somewhere on the middle of the left coast