All Products
Search
Document Center

PolarDB:ST_Transform

Last Updated:Mar 28, 2026

Transforms a trajectory from one spatial reference system (SRS) to another.

Syntax

trajectory ST_Transform(trajectory traj, int srid)

Parameters

ParameterTypeDescription
trajtrajectoryThe source trajectory to reproject. The trajectory must have an SRID.
sridintThe SRID of the target spatial reference system.
The trajectory can be transformed to the specified spatial reference only when the trajectory has an SRID.

Example

Reproject a trajectory from WGS 84 (SRID 4326) to a projected coordinate system (SRID 2401):

SELECT ST_Transform(
  '{"trajectory":{"version":1,"type":"STPOINT","leafcount":4,"start_time":"2020-11-03 08:00:00","end_time":"2020-11-03 18:03:20","spatial":"SRID=4326;LINESTRING(114.49211 37.97999,114.49211 37.97521,114.49191 37.98021,124 37)","timeline":["2020-11-03 08:00:00","2020-11-03 08:01:40","2020-11-03 08:03:20","2020-11-03 18:03:20"]}}'::trajectory,
  2401
);

Output:

{"trajectory":{"version":1,"type":"STPOINT","leafcount":4,"start_time":"2020-11-03 08:00:00","end_time":"2020-11-03 18:03:20","spatial":"SRID=2401;LINESTRING(29019418.8397 5025539.47515,29019696.5878 5024992.53808,29019387.9428 5025555.44863,29954166.377 5430882.06455)","timeline":["2020-11-03 08:00:00","2020-11-03 08:01:40","2020-11-03 08:03:20","2020-11-03 18:03:20"]}}