20.4 SDO_COVERS
Format
SDO_COVERS(geometry1, geometry2);
Description
Checks if any geometries in a table have the COVERS topological relationship with a specified geometry. Equivalent to specifying the SDO_RELATE operator with 'mask=COVERS'
.
See the section on the SDO_RELATE operator in this chapter for information about the operations performed by this operator and for usage requirements.
Keywords and Parameters
Value | Description |
---|---|
geometry1 |
Specifies a geometry column in a table. A spatial index on this column is recommended. Data type is SDO_GEOMETRY. |
geometry2 |
Specifies either a geometry from a table or a transient instance of a geometry. (Specified using a bind variable or SDO_GEOMETRY constructor.) Data type is SDO_GEOMETRY. |
Returns
The expression SDO_COVERS(geometry1,geometry2) = 'TRUE' evaluates to TRUE for object pairs that have the COVERS topological relationship, and FALSE otherwise.
Usage Notes
See the Usage Notes for the SDO_RELATE operator in this chapter.
For an explanation of the topological relationships and the nine-intersection model used by Spatial, see Spatial Relationships and Filtering.
For information about 3D support with spatial operators (which operators do and do not consider all three dimensions in their computations), see Three-Dimensional Spatial Objects.
Examples
The following example finds geometries that have the COVERS relationship with a query window (here, a rectangle with lower-left, upper-right coordinates 1,1, 4,6). (The example uses the definitions and data described and illustrated in Simple Example: Inserting_ Indexing_ and Querying Spatial Data.) In this example, only cola_a
covers the query window geometry.
SELECT c.mkt_id, c.name FROM cola_markets c WHERE SDO_COVERS(c.shape, SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1,1003,3), SDO_ORDINATE_ARRAY(1,1, 4,6)) ) = 'TRUE'; MKT_ID NAME ---------- -------------------------------- 1 cola_a
Parent topic: Spatial Operators