def compile_column(element, compiler, **kw):
if isinstance(element.table, (Table, Alias)):
if kw.has_key("within_columns_clause"
) and kw["within_columns_clause"] == True:
return compiler.process(functions.wkb(element))
return compiler.visit_column(element)
def main():
# Get db session.
session = sa_session.get_session()
# Clear cell tables
for t in [sa_cell.cell_habitat_table, sa_cell.cell_table]:
session.execute(t.delete())
session.commit()
# For each type of cell...
for cell_size in ["km100", "km1000"]:
print >>sys.stderr, "Processing cells of size '%s'" % cell_size
# Initialize list of cells.
cells = []
# Get cell ids
cell_id_attr = getattr(Habitat, "id_%s" % cell_size)
cell_area = func.sum(geo_func.area(func.geography(Habitat.geom))).label("cell_area")
cell_depth = func.avg(Habitat.z).label("cell_depth")
cell_geom_wkb = geo_func.wkb(func.st_union(Habitat.geom).label("cell_geom"))
cell_infos = session.query(cell_id_attr, cell_area, cell_depth, cell_geom_wkb).group_by(cell_id_attr).all()
# For each id, create cell and assign habitats.
print >>sys.stderr, "Creating cells"
cell_counter = 0
for (cell_id, cell_area, cell_depth, cell_geom_wkb) in cell_infos:
if (cell_counter % 1000) == 0:
print >>sys.stderr, "%s..." % (cell_counter),
cell_counter += 1
# Get cell's habitats.
cell_habitats = session.query(Habitat).filter(cell_id_attr == cell_id).all()
# Format cell's geometry.
cell_geom = wkb.loads("%s" % cell_geom_wkb)
if cell_geom.geom_type == "Polygon":
cell_geom = MultiPolygon([(cell_geom.exterior.coords, cell_geom.interiors)])
cell = Cell(
type=cell_size,
type_id=cell_id,
geom=cell_geom.wkt,
area=cell_area,
depth=cell_depth,
habitats=cell_habitats,
)
cells.append(cell)
session.add_all(cells)
session.commit()
def compile_column(element, compiler, **kw):
if isinstance(element.table, (Table, Alias)):
if kw.has_key("within_columns_clause") and kw["within_columns_clause"] == True:
if element.type.wkt_internal:
if isinstance(compiler.dialect, PGDialect):
return compiler.process(functions.wkt(element))
warnings.warn("WKT Internal GeometryColumn type not "
"compatible with %s dialect. Defaulting back to WKB"
% compiler.dialect.name, exc.SAWarning)
return compiler.process(functions.wkb(element))
return compiler.visit_column(element)
def compile_column(element, compiler, **kw):
if isinstance(element.table, (Table, Alias)):
if kw.has_key("within_columns_clause") and kw["within_columns_clause"] == True:
if element.type.wkt_internal:
if isinstance(compiler.dialect, PGDialect):
return compiler.process(functions.wkt(element))
warnings.warn("WKT Internal GeometryColumn type not "
"compatible with %s dialect. Defaulting back to WKB"
% compiler.dialect.name, exc.SAWarning)
return compiler.process(functions.wkb(element))
return compiler.visit_column(element)
def compile_column(element, compiler, **kw):
if isinstance(element.table, (Table, Alias)):
if kw.has_key("within_columns_clause") and kw["within_columns_clause"] == True:
return compiler.process(functions.wkb(element))
return compiler.visit_column(element)
