def __wrap_in_subquery(query_model):
"""
create an outer query containing the variables, select columns, offset, limit, order,
:param query_model:
:return:
"""
new_query_model = QueryModel()
new_query_model.variables = copy.copy(query_model.variables) # all prefixes are already in query_model1
new_query_model.from_clause = copy.copy(query_model.from_clause)
new_query_model.select_columns = copy.copy(query_model.select_columns)
new_query_model.offset = query_model.offset
new_query_model.limit = query_model.limit
new_query_model.order_clause = copy.copy(query_model.order_clause)
return new_query_model
def _outer_join(query_model1, query_model2):
joined_query_model = QueryModel()
joined_query_model.prefixes = copy.copy(
query_model1.prefixes) # all prefixes are already in query_model1
joined_query_model.variables = copy.copy(
query_model1.variables) # all prefixes are already in query_model1
joined_query_model.from_clause = copy.copy(query_model1.from_clause)
joined_query_model.select_columns = copy.copy(
query_model1.select_columns)
joined_query_model.offset = query_model1.offset
joined_query_model.limit = query_model1.limit
joined_query_model.order_clause = copy.copy(query_model1.order_clause)
QueryModel.clean_inner_qm(query_model1)
QueryModel.clean_inner_qm(query_model2)
joined_query_model.add_unions(query_model1)
joined_query_model.add_unions(query_model2)
return joined_query_model
def __join_expandable_grouped(self,
query_model1,
query_model2,
expandable_order=1):
if self.join_type == JoinType.OuterJoin: # outer join
return JoinOperator._outer_join(query_model1, query_model2)
elif self.join_type == JoinType.InnerJoin:
# add query model 2 as a subquery
QueryModel.clean_inner_qm(query_model2)
query_model1.add_subquery(query_model2)
return query_model1
elif ((expandable_order == 1 and self.join_type == JoinType.LeftOuterJoin) or\
(expandable_order == 2 and self.join_type == JoinType.RightOuterJoin)):
# make the subquery optional
QueryModel.clean_inner_qm(query_model2)
query_model1.add_optional_subquery(query_model2)
return query_model1
elif ((expandable_order == 2 and self.join_type == JoinType.LeftOuterJoin) or\
(expandable_order == 1 and self.join_type == JoinType.RightOuterJoin)):
# create an outer query and add the main dataset as a subquery and the optional dataset as optional subquery
joined_query_model = QueryModel()
joined_query_model.prefixes = copy.copy(
query_model1.prefixes
) # all prefixes are already in query_model1
joined_query_model.variables = copy.copy(
query_model1.variables
) # all prefixes are already in query_model1
joined_query_model.from_clause = copy.copy(
query_model1.from_clause)
joined_query_model.select_columns = copy.copy(
query_model1.select_columns)
joined_query_model.offset = query_model1.offset
joined_query_model.limit = query_model1.limit
joined_query_model.order_clause = copy.copy(
query_model1.order_clause)
QueryModel.clean_inner_qm(query_model1)
QueryModel.clean_inner_qm(query_model2)
joined_query_model.add_optional_subquery(query_model1)
joined_query_model.add_subquery(query_model2)
return joined_query_model
else:
raise Exception("Undefined case")
def __join_grouped_grouped(self, query_model1, query_model2):
joined_query_model = QueryModel()
joined_query_model.prefixes = copy.copy(
query_model1.prefixes) # all prefixes are already in query_model1
joined_query_model.add_prefixes(query_model2.prefixes)
joined_query_model.variables = copy.copy(
query_model1.variables.union(query_model2.variables)
) # all prefixes are already in query_model1
joined_query_model.from_clause = copy.copy(query_model1.from_clause)
joined_query_model.select_columns = copy.copy(
query_model1.select_columns.union(query_model2.select_columns))
joined_query_model.offset = min(query_model1.offset,
query_model2.offset)
joined_query_model.limit = max(query_model1.limit, query_model2.limit)
query_model1.order_clause.update(query_model2.order_clause)
joined_query_model.order_clause = copy.copy(query_model1.order_clause)
QueryModel.clean_inner_qm(query_model1)
QueryModel.clean_inner_qm(query_model2)
# add subqueries
if self.join_type == JoinType.InnerJoin:
joined_query_model.add_subquery(query_model1)
joined_query_model.add_subquery(query_model2)
elif self.join_type == JoinType.LeftOuterJoin:
joined_query_model.add_subquery(query_model1)
joined_query_model.add_optional_subquery(query_model2)
elif self.join_type == JoinType.RightOuterJoin:
joined_query_model.add_subquery(query_model2)
joined_query_model.add_optional_subquery(query_model1)
else: # outer join
joined_query_model.add_unions(query_model1)
joined_query_model.add_unions(query_model2)
return joined_query_model