Format

SDO_GEOR.hasGrayScale(
     georaster    IN SDO_GEORASTER, 
     layerNumber  IN NUMBER 
     ) RETURN VARCHAR2;

Description

Checks if a layer of a GeoRaster object has grayscale information.

Parameters

georaster

GeoRaster object.

layerNumber

Number of the layer to check. A value of 0 (zero) indicates the object layer.

Usage Notes

This function returns the string TRUE if the layer has grayscale information, or FALSE if the layer does not use grayscale representation. SDO_GEOR_GRAYSCALE Object Type describes grayscale display.

If the layer has grayscale information, you can get and set the grayscale mappings and the grayscale mapping table name. See the following: SDO_GEOR.getGrayScale and SDO_GEOR.getGrayScaleTable functions, and SDO_GEOR.setGrayScale and SDO_GEOR.setGrayScaleTable procedures.

Examples

The following example checks if layers 0 and 1 of a specified GeoRaster object (GEORASTER column) have grayscale information. (It refers to a table named GEORASTER_TABLE, whose definition is presented after Example 1-1 in Storage Parameters.)

SELECT substr(sdo_geor.hasGrayScale(georaster, 0),1,15) hasGrayScale0,
       substr(sdo_geor.hasGrayScale(georaster, 1),1,15) hasGrayScale1
  FROM georaster_table WHERE georid=4;

HASGRAYSCALE0   HASGRAYSCALE1
--------------- ---------------
TRUE            FALSE