[postgis-users] Getting data from table with interval
lucabert at lucabert.de
Thu Jan 6 12:41:34 PST 2022
I have a table in my PostGIS database, with the ground elevation of Europe.
The table is so:
gis=# \d elevation
Spalte | Typ | Sortierfolge | NULL erlaubt? | Vorgabewert
latlng | geography | | |
lat | double precision | | |
lng | double precision | | |
elevation | real | | |
lat and lng are just used for an export to a SQLite-DB for use in an
App. The same data are in "latlng" as geography...
The table has currently a precision of 3x3 Km, but I can import data
with a better precision, too, of course.
So my question...
I'd like to use these data to create a vertical profile similar to the
one I can get from Google-Maps.
Currently, with a simple query, I can get the elevation of a given point.
Of course, I don't have _all_ point in the table, so I have to search
the nearest point, but this is OK...
What I need is a function that receive two coordinates as parameters.
These coordinates define a line from A to B.
I'd like to retrieve all elevations in this line, with a given interval,
so that I can retrieve for example the elevation every kilometer or so.
And I don't have any idea how to do that...
Can someone suggest me a way?
Thanks a lot
(lucabert at lucabert.de)
More information about the postgis-users