This function sets the statistics about a specified band of a raster object.


raster ST_SetStatistics(raster rast, integer band, double min, double max, double mean, double std,cstring samplingParams);


Parameter Description
rast The raster object.
band The sequence number of the band, which starts from 0.
min,max,mean,std The statistics.
samplingParams The sampling parameters, which can be 'approx=false' or 'approx=true'.


update rast set rast=ST_SetStatistics(rast,0,0.0, 255.0, 125.0, 23.6, 'approx=false');

(1 row)