def visit_select(self, statement: AbstractStatement):
"""convertor for select statement
Arguments:
statement {AbstractStatement} -- [input select statement]
"""
# Create a logical get node
video = statement.from_table
if video is not None:
self.visit_table_ref(video)
# Filter Operator
predicate = statement.where_clause
if predicate is not None:
# Binding the expression
bind_predicate_expr(predicate)
filter_opr = LogicalFilter(predicate)
filter_opr.append_child(self._plan)
self._plan = filter_opr
# Projection operator
select_columns = statement.target_list
# ToDO
# add support for SELECT STAR
if select_columns is not None:
# Bind the columns using catalog
bind_columns_expr(select_columns)
projection_opr = LogicalProject(select_columns)
projection_opr.append_child(self._plan)
self._plan = projection_opr
def test_nested_implementation(self):
child_predicate = MagicMock()
root_predicate = MagicMock()
child_get_opr = LogicalGet(MagicMock(), MagicMock())
child_filter_opr = LogicalFilter(child_predicate, [child_get_opr])
child_project_opr = LogicalProject(MagicMock(), [child_filter_opr])
root_derived_get_opr = LogicalQueryDerivedGet([child_project_opr])
root_filter_opr = LogicalFilter(root_predicate, [root_derived_get_opr])
root_project_opr = LogicalProject(MagicMock(), [root_filter_opr])
opt_cxt, root_grp_id = self.top_down_rewrite(root_project_opr)
opt_cxt, root_grp_id = self.bottom_up_rewrite(root_grp_id, opt_cxt)
opt_cxt, root_grp_id = self.implement_group(root_grp_id, opt_cxt)
root_grp = opt_cxt.memo.groups[root_grp_id]
best_root_grp_expr = root_grp.get_best_expr(PropertyType.DEFAULT)
root_opr = best_root_grp_expr.opr
self.assertEqual(type(root_opr), SeqScanPlan)
self.assertEqual(root_opr.predicate, root_predicate)
child_grp_id = best_root_grp_expr.children[0]
child_grp = opt_cxt.memo.groups[child_grp_id]
best_child_grp_expr = child_grp.get_best_expr(PropertyType.DEFAULT)
child_opr = best_child_grp_expr.opr
self.assertEqual(type(child_opr), SeqScanPlan)
self.assertEqual(child_opr.predicate, child_predicate)
def test_should_visit_select_if_nested_query(self, mock_p, mock_c, mock_d):
m = MagicMock()
mock_p.return_value = mock_c.return_value = mock_d.return_value = m
stmt = Parser().parse(""" SELECT id FROM (SELECT data, id FROM video \
WHERE data > 2) WHERE id>3;""")[0]
converter = StatementToPlanConvertor()
actual_plan = converter.visit(stmt)
plans = [LogicalProject([TupleValueExpression('id')])]
plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_GREATER,
TupleValueExpression('id'),
ConstantValueExpression(3))))
plans.append(LogicalQueryDerivedGet())
plans.append(
LogicalProject(
[TupleValueExpression('data'),
TupleValueExpression('id')]))
plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_GREATER,
TupleValueExpression('data'),
ConstantValueExpression(2))))
plans.append(LogicalGet(TableRef(TableInfo('video')), m))
expected_plan = None
for plan in reversed(plans):
if expected_plan:
plan.append_child(expected_plan)
expected_plan = plan
self.assertEqual(expected_plan, actual_plan)
wrong_plan = plans[0]
for plan in plans[1:]:
wrong_plan.append_child(plan)
self.assertNotEqual(wrong_plan, actual_plan)
def test_should_not_call_insert_generator_for_other_types(
self, mock_class):
PlanGenerator().build(Operator(None))
PlanGenerator().build(Operator(LogicalFilter(None)))
PlanGenerator().build(Operator(LogicalGet(None, 1)))
PlanGenerator().build(Operator(LogicalProject([])))
mock_class.assert_not_called()
def test_should_return_correct_plan_tree_for_input_logical_tree(self):
logical_plan = LogicalProject(
[1, 2], [LogicalFilter("a", [LogicalGet("video", 1)])])
plan = ScanGenerator().build(logical_plan)
self.assertTrue(isinstance(plan, SeqScanPlan))
self.assertEqual("a", plan.predicate)
self.assertEqual([1, 2], plan.columns)
self.assertEqual(PlanNodeType.STORAGE_PLAN, plan.children[0].node_type)
self.assertEqual(1, plan.children[0].video)
def test_simple_project_into_derived_get(self):
rule = EmbedProjectIntoDerivedGet()
target_list = MagicMock()
logi_derived_get = LogicalQueryDerivedGet([Dummy()])
logi_project = LogicalProject(target_list, [logi_derived_get])
rewrite_opr = rule.apply(logi_project, MagicMock())
self.assertEqual(rewrite_opr, logi_derived_get)
self.assertEqual(rewrite_opr.target_list, target_list)
def test_pushdown_project_thru_sample(self):
rule = PushdownProjectThroughSample()
target_list = MagicMock()
constexpr = MagicMock()
logi_get = LogicalGet(MagicMock(), MagicMock(), [Dummy()])
sample = LogicalSample(constexpr, [logi_get])
logi_project = LogicalProject(target_list, [sample])
rewrite_opr = rule.apply(logi_project, MagicMock())
self.assertEqual(rewrite_opr, sample)
self.assertEqual(rewrite_opr.children[0].target_list, target_list)
def test_simple_project_into_get(self):
rule = EmbedProjectIntoGet()
expr1 = MagicMock()
expr2 = MagicMock()
expr3 = MagicMock()
logi_get = LogicalGet(MagicMock(), MagicMock())
logi_project = LogicalProject([expr1, expr2, expr3], [logi_get])
rewrite_opr = rule.apply(logi_project, MagicMock())
self.assertEqual(rewrite_opr, logi_get)
self.assertEqual(rewrite_opr.target_list, [expr1, expr2, expr3])
def test_should_visit_select_union_if_union_query(self, mock_p, mock_c,
mock_d):
m = MagicMock()
mock_p.return_value = mock_c.return_value = mock_d.return_value = m
stmt = Parser().parse(""" SELECT id FROM video WHERE id>3
UNION ALL
SELECT id FROM video WHERE id<=3;""")[0]
converter = StatementToPlanConvertor()
actual_plan = converter.visit(stmt)
left_plans = [LogicalProject([TupleValueExpression('id')])]
left_plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_GREATER,
TupleValueExpression('id'),
ConstantValueExpression(3))))
left_plans.append(LogicalGet(TableRef(TableInfo('video')), m))
def reverse_plan(plans):
return_plan = None
for plan in reversed(plans):
if return_plan:
plan.append_child(return_plan)
return_plan = plan
return return_plan
expect_left_plan = reverse_plan(left_plans)
right_plans = [LogicalProject([TupleValueExpression('id')])]
right_plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_LEQ,
TupleValueExpression('id'),
ConstantValueExpression(3))))
right_plans.append(LogicalGet(TableRef(TableInfo('video')), m))
expect_right_plan = reverse_plan(right_plans)
expected_plan = LogicalUnion(True)
expected_plan.append_child(expect_right_plan)
expected_plan.append_child(expect_left_plan)
self.assertEqual(expected_plan, actual_plan)
def test_nested_bottom_up_rewrite(self):
child_predicate = MagicMock()
root_predicate = MagicMock()
child_get_opr = LogicalGet(MagicMock(), MagicMock())
child_filter_opr = LogicalFilter(child_predicate, [child_get_opr])
child_project_opr = LogicalProject(MagicMock(), [child_filter_opr])
root_derived_get_opr = LogicalQueryDerivedGet([child_project_opr])
root_filter_opr = LogicalFilter(root_predicate, [root_derived_get_opr])
root_project_opr = LogicalProject(MagicMock(), [root_filter_opr])
opt_cxt, root_grp_id = self.top_down_rewrite(root_project_opr)
opt_cxt, root_grp_id = self.bottom_up_rewrite(root_grp_id, opt_cxt)
grp_expr = opt_cxt.memo.groups[root_grp_id].logical_exprs[0]
self.assertEqual(type(grp_expr.opr), LogicalQueryDerivedGet)
self.assertEqual(len(grp_expr.opr.children), 1)
self.assertEqual(grp_expr.opr.predicate, root_predicate)
test_child_opr = grp_expr.opr.children[0]
self.assertEqual(type(test_child_opr), LogicalGet)
self.assertEqual(test_child_opr.predicate, child_predicate)
def test_nested_top_down_rewrite(self):
child_predicate = MagicMock()
root_predicate = MagicMock()
child_get_opr = LogicalGet(MagicMock(), MagicMock())
child_filter_opr = LogicalFilter(child_predicate, [child_get_opr])
child_project_opr = LogicalProject(MagicMock(), [child_filter_opr])
root_derived_get_opr = LogicalQueryDerivedGet([child_project_opr])
root_filter_opr = LogicalFilter(root_predicate, [root_derived_get_opr])
root_project_opr = LogicalProject(MagicMock(), [root_filter_opr])
opt_cxt, root_grp_id = self.top_down_rewrite(root_project_opr)
grp_expr = opt_cxt.memo.groups[root_grp_id].logical_exprs[0]
# rewrite happens in a way that new expression is
# inserted in a new group
self.assertEqual(type(grp_expr.opr), LogicalProject)
self.assertEqual(len(grp_expr.opr.children), 1)
test_child_opr = grp_expr.opr.children[0]
self.assertEqual(type(test_child_opr), LogicalFilter)
self.assertEqual(len(test_child_opr.children), 1)
self.assertEqual(test_child_opr.predicate, root_predicate)
test_child_opr = test_child_opr.children[0]
self.assertEqual(type(test_child_opr), LogicalQueryDerivedGet)
self.assertEqual(len(test_child_opr.children), 1)
test_child_opr = test_child_opr.children[0]
self.assertEqual(type(test_child_opr), LogicalProject)
self.assertEqual(len(test_child_opr.children), 1)
test_child_opr = test_child_opr.children[0]
self.assertEqual(type(test_child_opr), LogicalGet)
self.assertEqual(test_child_opr.predicate, child_predicate)
def test_visit_select_orderby(self, mock_p, mock_c, mock_d):
m = MagicMock()
mock_p.return_value = mock_c.return_value = mock_d.return_value = m
stmt = Parser().parse(""" SELECT data, id FROM video \
WHERE data > 2 ORDER BY data, id DESC;""")[0]
converter = StatementToPlanConvertor()
actual_plan = converter.visit(stmt)
plans = []
plans.append(
LogicalOrderBy([
(TupleValueExpression('data'), ParserOrderBySortType.ASC),
(TupleValueExpression('id'), ParserOrderBySortType.DESC)
]))
plans.append(
LogicalProject(
[TupleValueExpression('data'),
TupleValueExpression('id')]))
plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_GREATER,
TupleValueExpression('data'),
ConstantValueExpression(2))))
plans.append(LogicalGet(TableRef(TableInfo('video')), m))
expected_plan = None
for plan in reversed(plans):
if expected_plan:
plan.append_child(expected_plan)
expected_plan = plan
self.assertEqual(expected_plan, actual_plan)
wrong_plan = plans[0]
for plan in plans[1:]:
wrong_plan.append_child(plan)
self.assertNotEqual(wrong_plan, actual_plan)
def test_visit_select_sample(self, mock_p, mock_c, mock_d):
m = MagicMock()
mock_p.return_value = mock_c.return_value = mock_d.return_value = m
stmt = Parser().parse(""" SELECT data, id FROM video SAMPLE 2 \
WHERE id > 2 LIMIT 3;""")[0]
converter = StatementToPlanConvertor()
actual_plan = converter.visit(stmt)
plans = []
plans.append(LogicalLimit(ConstantValueExpression(3)))
plans.append(
LogicalProject(
[TupleValueExpression('data'),
TupleValueExpression('id')]))
plans.append(
LogicalFilter(
ComparisonExpression(ExpressionType.COMPARE_GREATER,
TupleValueExpression('id'),
ConstantValueExpression(2))))
plans.append(LogicalSample(ConstantValueExpression(2)))
plans.append(
LogicalGet(
TableRef(TableInfo('video'), ConstantValueExpression(2)), m))
expected_plan = None
for plan in reversed(plans):
if expected_plan:
plan.append_child(expected_plan)
expected_plan = plan
self.assertEqual(expected_plan, actual_plan)
def test_should_return_use_scan_generator_for_logical_project(self,
mock_class):
mock_instance = mock_class.return_value
l_project = LogicalProject([])
PlanGenerator().build(l_project)
mock_instance.build.assert_called_with(l_project)
def _visit_projection(self, select_columns):
# Bind the columns using catalog
bind_columns_expr(select_columns, self._column_map)
projection_opr = LogicalProject(select_columns)
projection_opr.append_child(self._plan)
self._plan = projection_opr