STS_TrajectoryIntersect function
The STS_TrajectoryIntersect function indicates whether the trajectory of an object intersected the region during the time range.
Syntax
STS_TrajectoryIntersect(
ts TimeSeries,
begin_time DATETIME YEAR TO FRACTION(5),
end_time DATETIME YEAR TO FRACTION(5),
geometry ST_Geometry)
returns Boolean- ts
- The name of the time series.
- begin_time
- The start of the time range. Can be NULL to indicate the first element in the time series.
- end_time
- The end of the time range. Can be NULL to indicate the last element in the time series.
- geometry
- The region of interest. Can be an ST_Point, ST_MultiPoint, ST_LineString, ST_MultiLineString, ST_Polygon, or ST_MultiPolygon. Must use the SRID 4326.
Usage
Run the STS_TrajectoryIntersect function to find out whether the specified object moved through the specified region during the specified time range. Intersection means either crossed the boundary of the region or remained within the boundary of the region.
The following image shows a trajectory that crosses the boundary of a region.
The following image shows a trajectory that is entirely within a region.
Returns
t = The trajectory of the object crossed the boundary of the region during the time range.
t = The trajectory of the object remained within the region during the time range.
f = The trajectory of the object did not intersect the region during the time range.
An exception = An error.
Example
The following query returns whether any vehicles intersected the specified region between the times 2015-06-14 12:30:00 and 2015-06-14 13:00:00:
SELECT modid, STS_TrajectoryIntersect(ts_track,
'2015-06-14 12:30:00', '2015-06-14 13:00:00',
ST_Buffer('4326 point(-78.704122 43.919747)', 100.0, 'meter'))
FROM t_vehicle;
modid (expression)
1001 f
1002 t
2 row(s) retrieved.Vehicle 1002 intersected the region.