slope and area constraints on multiple contiguous polygons

slope_area3

Drop view slope_area3;
create or replace view slope_area3 as 
select gid::integer, new_geom, area_hectare from
(select generate_series(1, ST_NumGeometries(mymulti)) as gid, 
	ST_GeometryN(mymulti, generate_series(1, ST_NumGeometries(mymulti))) as new_geom,
	st_area(ST_GeometryN(mymulti, generate_series(1, ST_NumGeometries(mymulti)))) 
	/10000 AS area_hectare
	from (select max(gid) as gid, st_memunion(the_geom) as mymulti 
		from 
		(select * from parcel_stats 
		where max_slope < 20
		and st_intersects(st_buffer(st_geomfromtext('POINT(7501221 4674923)', 97392), 1500),parcel_stats.the_geom))
		as t1) as t2
		--group by gid
		) as t3
where area_hectare >= 40;