ST_Value-AnalyticDB(AnalyticDB)-阿里云帮助中心

Returns the value of a cell at the specified band, column, and row in a raster object.

Syntax

float8 ST_Value(raster rast, integer band, integer colsn, integer rowsn, boolean exclude_nodata_value);

Parameter	Description
`rast`	The raster object.
`band`	The band number. Band numbers start at 0. Default: `0`.
`colsn`	The column number of the cell. Default: `0`.
`rowsn`	The row number of the cell. Default: `0`.
`exclude_nodata_value`	Specifies whether to exclude NoData values. Default: `true`.

Band numbers start at 0. The default band number, column number, and row number are all 0.

Retrieve the value of the cell at column 3, row 4 in band 1 of the raster object stored in the t_pixel table:

SELECT ST_Value(rast, 1, 3, 4) FROM t_pixel WHERE id = 2;
 st_value
----------
       88
(1 row)