def select(self,cols="*"):
if cols:
if cols == '*':
cols = ','.join(self.__schema__)
self.col_exps = codd.parse(
"({})".format(cols),
get_value=self.get_value
).func_closure[0].cell_contents
#self.col_exps = [
# codd.parse(col, get_value=self.get_value)
# for col in cols
#]
self.reducers = [
(pos, self.aggregates[col.__name__])
for pos, col in enumerate(self.col_exps)
if col.__name__ in self.aggregates
]
self.schema = [
getattr(c, '__name__', "col{}".format(i))
for i,c in enumerate(self.col_exps)
]
result_class = self.result_class = namedtuple("row", self.schema)
return self
def _order_key(self, attr, direction="desc"):
direction = direction.lower()
get_key = codd.parse(attr)
if direction == "desc":
return get_key
elif direction == "asc":
def invert(record, ctx):
value = get_key(record,ctx)
v_type = type(value)
# TODO: utilize types if/when we get them
if v_type in (int, float, long, complex):
return -value
elif v_type in ( str, bytearray):
return [-b for b in bytearray(value)]
elif v_type == unicode:
return [-b for b in bytearray(value.encode('utf-8'))]
else:
return None
return invert
else:
raise RuntimeError("direction must be DESC or ASC")
