STS_GetLocWithin function

The STS_GetLocWithin function returns the set of objects whose trajectory is within the specified region during the specified time range.

Syntax


STS_GetLocWithin(
                    subtrack_name   VARCHAR(128),
                    begin_time      DATETIME YEAR TO FRACTION(5),
                    end_time        DATETIME YEAR TO FRACTION(5),
                    geometry        ST_Geometry)
returns ROW

subtrack_name: The name of the subtrack table.
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_GetLocWithin function to find which objects were moving in a region at a specific time. The trajectory of an object must intersect the region and the object must have a recorded position within the region to be returned by the STS_GetLocWithin function.

Returns

A set of primary key values = The objects that were moving in the region.

NULL = Nothing found.

Example

The following statement returns which vehicles moved within the specified region between the times of 2014-06-10 16:30:00 and 2014-06-10 17:00:00:

SELECT * from TABLE(STS_GetLocWithin('t_vehicle_subtrack', 
         '2014-06-10 16:30:00', '2014-06-10 17:00:00',
         ST_Buffer('4326 POINT(-78.752717 43.922478)'::ST_Point, 
                   640, 'meter'))::row(modid varchar(60))) 
         AS t(mid);

mid  ROW('1001')

1 row(s) retrieved.

Vehicle 1001 was in the region.