ST_Count

ST_Count
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Name

ST_Count — Returns the number of pixels in a given band of a raster or raster coverage. If no band is specified defaults to band 1. If exclude_nodata_value is set to true, will only count pixels that are not equal to the nodata value.

Synopsis

bigint ST_Count(raster rast, integer nband=1, boolean exclude_nodata_value=true);

bigint ST_Count(raster rast, boolean exclude_nodata_value);

bigint ST_Count(text rastertable, text rastercolumn, integer nband=1, boolean exclude_nodata_value=true);

bigint ST_Count(text rastertable, text rastercolumn, boolean exclude_nodata_value);

Description

Returns the number of pixels in a given band of a raster or raster coverage. If no band is specified nband defaults to 1.


	If `exclude_nodata_value` is set to true, will only count pixels with value not equal to the `nodata` value of the raster. Set `exclude_nodata_value` to false to get count all pixels

Availability: 2.0.0


	The ST_Count(rastertable, rastercolumn, ...) variants are deprecated as of 2.2.0. Use ST_CountAgg instead.

Examples

--example will count all pixels not 249 and one will count all pixels.  --
SELECT rid, ST_Count(ST_SetBandNoDataValue(rast,249)) As exclude_nodata,
        ST_Count(ST_SetBandNoDataValue(rast,249),false) As include_nodata
    FROM dummy_rast WHERE rid=2;

rid | exclude_nodata | include_nodata
-----+----------------+----------------
   2 |             23 |             25

Name

Synopsis

Description

Examples

See Also