def join(self,
table: Table,
on: EXPRESSION_TYPE = None,
using: Column = None,
full_cartesian: bool = False):
join = "join {table}".format(table=table.str()) # unsafe formatting
assert on is None or using is None, "both 'on' and 'using' cannot be specified at the same time"
if on is not None:
join += " on {on}".format(on=ExpressionParser.parse(on).str())
elif using is not None:
join += " using ({using})".format(using=using.name)
elif not full_cartesian:
raise Exception(
"Trying to create a join without adding 'on' nor 'using' clauses. "
"This results in a full cartesian product of both tables, "
"and that is probably not what you want to achieve. "
"To avoid it, set either an 'on' condition or a 'using' column. "
"If you really want to perform the full cartesian product, "
"set the 'full_cartesian' parameter to true.")
if self._not_none(self._join):
self._join += " " + join
else:
self._join = join
return self
def table(self, table: Table):
self._from = "from {table}".format(
table=table.str()) # unsafe formatting
return self
def table(self, table: Table):
self._table = table.str()
return self