PostGIS 常用语句

---获取myTable图层的要素范围，将值以数组形式存在metaTable表的extent字段中
update metaTable
set extent = (select array [st_xmin(t.box), st_ymin(t.box), st_xmax(t.box), st_ymax(t.box)]
              from (select st_extent(geom) as box
                    from myTable) as t)
where name = 'myTable';