how can I lower the resolution of my raster image in PostGIS? And does someone has an example for that operation? I am trying to import raster images with raster2pgsql, I suppose that there is a tag, that manages that problem but I am not sure about it.
I have got the answer , although nobody helped me. The solution is to use the -l flag during importing the raster with raster2pgsql. The -l flag is used for creating owerviews in different zoom level but it is also helpful for lower the resolution of an raster image.