[postgis-users] Mixing SRID's

[Markus Schaber]

Hi, Johan,

Johan Wehtje wrote:
> I have tried using SRID 4326, but I
> run into the same scale problem i ran into earlier because apparently
> this SRID is projected.

Well, for inserting data that is in e. G. SRID 4711 into a SRID 4326
column, you have to use transform(setsrid(geom),4711),4326).

SRID 4326 is WGS84, latitude/longitude data in degrees (and thus is not
projected).

Which tool did you use to view your data? Maybe this tool must be
configured to use the correct projection.

> But when I do a like search on WGS84 I get
> hundreds of resuts, and reading the srtext and proj4 feilds to try and
> figure out which SRID I should be using is not especially user freindly.
> Is there somewhere where I can egt a list of the more common datums that
> I can check my database agaoinst.

You should try to check your input data sources documentation which
formats they deliver, some GPS receivers display the data reprojected
into some UTM or Gauss-Krueger zones by default, although they all work
with WGS84 internally.

Looking into the EPSG database may also help, as their database is the
source for all the PostGIS SRIDs, but it is more verbose.

Markus