Clustering data in Google Earth

Hi,
 I have thousands of places of interest which I want to show
in Google
Maps or Google Earth. I will have coordinates and other data
in e.g. a
MySQL database (could also be PostgresQL/PostGIS).

In my application, I will do querys to the database to get
points
within a certain bounding box. Now, if I have up to 100
points, that's
OK - I can show all the datapoints. However, if the bounding
box is
large, and there are several thousand points within the
bounding box, I
cannot show all datapoints. I will then have to cluster or
group the
datapoints based on geography. I am searching for a simple
way (a
single query from the database if possible) to give me up to
100 groups
of points instead of every single point. Is there a simple
way to do
this? I guess this should be a very common task in a GIS,
but I
couldn't find any info on how to do this when doing a few
searches. I
am planning to use PHP to access the database.

Jan

I used to read some technic that they writing the refresh
period for
GE, then the GE able to send back the data that where u r
watching on
earth. After that, PHP will use that location to query only
nearby
area.

If someone able to describe this technic in more details
would be good,

Hope it might helps.

Max

On 12/19/05, Jan.Kocbach <jan.kocbachgmail.com> wrote:
>
> Hi,
>  I have thousands of places of interest which I want to
show in Google
> Maps or Google Earth. I will have coordinates and other
data in e.g. a
> MySQL database (could also be PostgresQL/PostGIS).
>
> In my application, I will do querys to the database to
get points
> within a certain bounding box. Now, if I have up to 100
points, that's
> OK - I can show all the datapoints. However, if the
bounding box is
> large, and there are several thousand points within the
bounding box, I
> cannot show all datapoints. I will then have to cluster
or group the
> datapoints based on geography. I am searching for a
simple way (a
> single query from the database if possible) to give me
up to 100 groups
> of points instead of every single point. Is there a
simple way to do
> this? I guess this should be a very common task in a
GIS, but I
> couldn't find any info on how to do this when doing a
few searches. I
> am planning to use PHP to access the database.
>
> Jan
>
>


--
max
phone: +66 6810 8088
msn: maxsd30.net
skype: teerachart

Sorry to answer your question with a question...
I only want to track about 100 points that may change daily
and your
question implies there's a simple way to do this by
populating the
points from a database table. Can you push me to somewhere I
can find
out how to do this?
Thanks,
lq

Sorry to answer your question with a question...
I only want to track about 100 points that may change daily
and your
question implies there's a simple way to do this by
populating the
points from a database table. Can you push me to somewhere I
can find
out how to do this?
Thanks,
lq