SELECT ST_BUFFER( <geometry_field>, <tollerance>) from dataset_XXXX;
Examples (on a dataset named dataset_12313 with the geometry field named wkb_geometry):
This will buffer the geometry 0.005 of a degree. that's a few city blocks around north america.
SELECT ST_BUFFER( wkb_geometry, 0.005) as wkb_geometry from dataset_12313;
Here is another example using 10 meters. We convert it to a geography type, buffer by 10 meters and then convert it back to a geometry type for AmigoCloud to display on the map:
SELECT ST_BUFFER( wkb_geometry::geography, 10)::geometry as wkb_geometry from dataset_12312;