This topic describes the ST_cumulativeDistanceAtTime function. This function is used to compute the cumulative distance that a trajectory object covers when it moves from a specified position until a specified point in time arrives.


float8 ST_cumulativeDistanceAtTime(trajectory traj, timestamp t);


Parameter Description
traj The trajectory object whose movement distance you want to compute.
t The point in time at which the trajectory object stops moving.


Select ST_cumulativeDistanceAtTime(traj, '2011-11-1 04:30:00') from traj_table;