The area and length of features are not pre-calculated and stored by Oracle’s SDO_GEOMETRY data type constructor functions. SDO_GEOMETRY type does not have places to store area and length values.
Geometric functions SDO_GEO.SDO_AREA and SDO_GEOM.SDO_LENGTH can be used to calculate the values in SQL queries when needed.
-- calculate the area
SELECT OBJECTID, SDO_GEOM.SDO_AREA(SHAPE, 0.005) FROM THE_LAYER;
-- calculate the length
SELECT OBJECTID, SDO_GEOM.SDO_LENGTH(SHAPE, 0.005) FROM THE_LAYER;
0.005 is the tolerance.
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