This example computes the union of area for both the gates and the terminals.
Input
Input tables are from GeometryOverlay Example 1: Intersection:
- source: source_gatetype, which contains the geometrical coordinates of US and international gates in three airport terminals (A, B, and C)
- reference: ref_terminal, which contains the terminal coordinates in WKT syntax
SQL Call
SELECT * FROM GeometryOverlay (
ON source_gatetype AS source PARTITION BY id
ON ref_terminal AS reference PARTITION BY id
USING
SourceLocationColumn ('boundary_coordinates')
ReferenceLocationColumn ('boundary_coordinates')
ReferenceNameColumns ('boundary_name')
BoundaryOperator ('union')
OutputAll ('false')
Accumulate ('boundary_name', 'id')
) AS dt ORDER BY 2, 1;
Output
Because all US gates are within Terminal A, the union of the area specified by the domestic gates and the area of Terminal A is just Terminal A, as shown in the first row of the output. The second row shows the union of the coordinates of the international gates and all three terminals.
| overlay_boundary | ref_boundary_name | overlay_flag | boundary_name | id |
|---|---|---|---|---|
| POLYGON ((0 0, 0 100, 100 100, 100 0, 0 0)) | Terminal A | 1 | US Gates | 1 |
| POLYGON ((50 50, 50 150, 150 150, 150 100, 200 100, 200 0, 100 0, 100 50, 50 50)) | Terminal B | 1 | International Gates | 2 |