SDO_TOUCH

Format

SDO_TOUCH(geometry1, geometry2);

Description

Checks if any geometries in a table have the TOUCH topological relationship with a specified geometry. Equivalent to specifying the SDO_RELATE operator with 'mask=TOUCH'.

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_TOUCH(geometry1,geometry2) = 'TRUE' evaluates to TRUE for object pairs that have the TOUCH 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 TOUCH relationship with a query window (here, a rectangle with lower-left, upper-right coordinates 1,1, 5,7). (The example uses the definitions and data in Simple Example: Inserting_ Indexing_ and Querying Spatial Data.) In this example, only cola_b has the TOUCH relationship with the query window geometry.

SELECT c.mkt_id, c.name
  FROM cola_markets c
  WHERE SDO_TOUCH(c.shape,
            SDO_GEOMETRY(2003, NULL, NULL,
              SDO_ELEM_INFO_ARRAY(1,1003,3),
              SDO_ORDINATE_ARRAY(1,1, 5,7))
            ) = 'TRUE';
  FROM cola_markets c

    MKT_ID NAME       
---------- --------------------------------                             
         2 cola_b