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

Returns true if the distance between two trajectory objects within the specified time range is within the reference distance.

Syntax

boolean ST_distanceWithin(trajectory traj1, trajectory traj2, tsrange range, float8 d);
boolean ST_distanceWithin(trajectory traj1, trajectory traj2, timestamp t1, timestamp t2, float8 d);

Parameters

Parameter	Type	Description
`traj1`, `traj2`	`trajectory`	The trajectory objects to compare.
`range`	`tsrange`	The time range to check. Use either this parameter or `t1`/`t2`, not both.
`t1`	`timestamp`	The start of the time range.
`t2`	`timestamp`	The end of the time range.
`d`	`float8`	The reference distance.

Examples

Check whether two vehicles come within 100 meters of each other between 13:00 and 14:00:

SELECT ST_distanceWithin(
  (SELECT traj FROM traj_table WHERE id = 1),
  (SELECT traj FROM traj_table WHERE id = 2),
  '2010-1-1 13:00:00',
  '2010-1-1 14:00:00',
  100
);

Use a tsrange value to check proximity within a time window:

SELECT ST_distanceWithin(
  (SELECT traj FROM traj_table WHERE id = 1),
  (SELECT traj FROM traj_table WHERE id = 2),
  '[2010-01-01 13:00:00, 2010-01-01 14:00:00]'::tsrange,
  100
);