35.89 SDO_UTIL.VALIDATE_WKTGEOMETRY
Format
SDO_UTIL.VALIDATE_WKTGEOMETRY( geometry IN CLOB ) RETURN VARCHAR2;
or
SDO_UTIL.VALIDATE_WKTGEOMETRY( geometry IN VARCHAR2 ) RETURN VARCHAR2;
Description
Validates the input geometry, which is of type CLOB or VARCHAR2 and in the standard
well-known text (WKT or EWKT) format; returns the string
TRUE
if the input is valid, or FALSE
if the input is not valid WKT or EWKT.
Usage Notes
Note:
The SDO_UTIL.VALIDATE_WKTGEOMETRY function is supported only if Oracle JVM is enabled on your Oracle Autonomous Database Serverless deployments. To enable Oracle JVM, see Use Oracle Java in Using Oracle Autonomous Database Serverless for more information.To be valid, the input geometry may be in the well-known text (WKT) format, or in the EWKT format.
This function is patterned after the SQL Multimedia recommendations in ISO 13249-3, Information technology - Database languages - SQL Multimedia and Application Packages - Part 3: Spatial.
To validate a geometry in the well-known binary (WKB) format, use the SDO_UTIL.VALIDATE_WKBGEOMETRY function.
Examples
The following example shows conversion to and from WKB and WKT format, and validation of WKB and WKT geometries. (The example uses the definitions and data from Simple Example: Inserting_ Indexing_ and Querying Spatial Data, specifically the cola_b
geometry from the COLA_MARKETS table.)
DECLARE wkbgeom BLOB; wktgeom CLOB; val_result VARCHAR2(5); geom_result SDO_GEOMETRY; geom SDO_GEOMETRY; BEGIN SELECT c.shape INTO geom FROM cola_markets c WHERE c.name = 'cola_b'; -- To WBT/WKT geometry wkbgeom := SDO_UTIL.TO_WKBGEOMETRY(geom); wktgeom := SDO_UTIL.TO_WKTGEOMETRY(geom); DBMS_OUTPUT.PUT_LINE('To WKT geometry result = ' || TO_CHAR(wktgeom)); -- From WBT/WKT geometry geom_result := SDO_UTIL.FROM_WKBGEOMETRY(wkbgeom); geom_result := SDO_UTIL.FROM_WKTGEOMETRY(wktgeom); -- Validate WBT/WKT geometry val_result := SDO_UTIL.VALIDATE_WKBGEOMETRY(wkbgeom); DBMS_OUTPUT.PUT_LINE('WKB validation result = ' || val_result); val_result := SDO_UTIL.VALIDATE_WKTGEOMETRY(wktgeom); DBMS_OUTPUT.PUT_LINE('WKT validation result = ' || val_result); END;/ To WKT geometry result = POLYGON ((5.0 1.0, 8.0 1.0, 8.0 6.0, 5.0 7.0, 5.0 1.0)) WKB validation result = TRUE WKT validation result = TRUE
Parent topic: SDO_UTIL Package (Utility)