It is possible to store details of the origin of the geopoints data in its file. The following example shows the meta-information generated by an ODB query.
#GEO lat long level date time value #DB_INFO DB_SYSTEM: ODB DB_COLUMN: lldegrees(lat@hdr);lldegrees(lon@hdr); ; ; ;obsvalue@body DB_COLUMN_ALIAS: lldegrees(lat);lldegrees(lon); ; ; ;obsvalue@body DB_PATH: /tmp/cgi/odb/ECMA.conv DB_QUERY_BEGIN select lldegrees(lat), lldegrees(lon), obsvalue from hdr, body where varno=$t2m and obsvalue is not null DB_QUERY_END #DATA 36.150 -5.350 0.000 0 0000 295.10000000
Currently, ODB is the only database system to generate this meta-information. It is not discussed in detail here because it is generated automatically. Macro functions exist to extract this information from a geopoints variable - see Geopoints Functions.