3.6 Validating GeoRaster Objects

Before you use a GeoRaster object or after you manually edit the raster data and metadata of a GeoRaster object, you should ensure that the object is valid. Validation for a GeoRaster object includes checking the registration of the GeoRaster object, checking the metadata and the raster cell data, and making sure that the metadata and data are consistent. For example, validation checks the raster type, dimension information, and the actual sizes of cell blocks, and it performs other checks.

If you used the GeoRaster loader tool described in GeoRaster Tools: Viewer_ Loader_ Exporter, the GeoRaster objects were validated during the load operation.

GeoRaster provides the following validation subprograms:

• SDO_GEOR.validateGeoRaster validates the GeoRaster object, including cell data and metadata. It returns TRUE if the object is valid; otherwise, it returns one of the following: an Oracle error code indicating why the GeoRaster object is invalid, FALSE if validation fails for an unknown reason, or NULL if the GeoRaster object is null. You should always use this function after you create a GeoRaster object.

• SDO_GEOR.schemaValidate validates the metadata against the GeoRaster XML schema. You can use this function to locate errors if the SDO_GEOR.validateGeoRaster function returned the error code 13454. The SDO_GEOR.schemaValidate and SDO_GEOR.validateGeoRaster functions do not validate the spatial extent geometry.

• SDO_GEOR.validateBlockMBR validates the blockMBR geometry associated with each raster block stored in the raster data table. If there are any invalid blockMBR geometries, call the SDO_GEOR.generateBlockMBR procedure to regenerate them.