ST_nearestApproachDistance-ApsaraDB RDS(RDS)-阿里云帮助中心

Returns the nearest approach distance between a trajectory object and a geometry object within a specified time range.

Syntax

float8 ST_nearestApproachDistance(trajectory traj, tsrange range, geometry g);
float8 ST_nearestApproachDistance(trajectory traj, timestamp t1, timestamp t2, geometry g);

Parameters

Parameter	Type	Description
`traj`	trajectory	The trajectory object to evaluate.
`range`	tsrange	The time range.
`t1`	timestamp	The start time.
`t2`	timestamp	The end time.
`g`	geometry	The geometry object to measure distance from.

Example

The following query returns the nearest approach distance between the trajectory in each row of traj_table and the line LINESTRING(0 0, 5 5, 9 9), considering only the portion of the trajectory between 13:00 and 14:00 on January 1, 2010.

SELECT ST_nearestApproachDistance(
    traj,
    '2010-1-1 13:00:00',
    '2010-1-1 14:00:00',
    'LINESTRING(0 0, 5 5, 9 9)'::geometry
)
FROM traj_table;