def test_potential_indexes(self):
index_set_1 = set([Index([column_A_0])])
index_set_2 = set(
[Index([column_A_0]),
Index([column_A_1]),
Index([column_A_2])])
self.assertEqual(
set(
Workload([query_0],
database_name="test_DB").potential_indexes()),
index_set_1,
)
self.assertEqual(
set(
Workload([query_1],
database_name="test_DB").potential_indexes()),
index_set_2,
)
self.assertEqual(
set(
Workload([query_0, query_1],
database_name="test_DB").potential_indexes()),
index_set_2,
)
def setUpClass(cls):
cls.db_name = "tpch_test_db_index_selection"
cls.index_selection = IndexSelection()
db = PostgresDatabaseConnector(None, autocommit=True)
SCALE_FACTOR = 0.001
table_generator = TableGenerator("tpch",
SCALE_FACTOR,
db,
explicit_database_name=cls.db_name)
db.close()
cls.index_selection.setup_db_connector(cls.db_name, "postgres")
# Filter worklaod
query_generator = QueryGenerator(
"tpch",
SCALE_FACTOR,
cls.index_selection.db_connector,
[3, 14],
table_generator.columns,
)
cls.small_tpch = Workload(query_generator.queries)
query_generator = QueryGenerator(
"tpch",
SCALE_FACTOR,
cls.index_selection.db_connector,
[5, 6],
table_generator.columns,
)
cls.tpch_5_and_6 = Workload(query_generator.queries)
def test_workload_indexable_columns(self):
table = Table("TableA")
column_1 = Column(name="ColA")
column_2 = Column(name="ColB")
column_3 = Column(name="ColC")
table.add_column(column_1)
table.add_column(column_2)
table.add_column(column_3)
query_1 = Query(
17,
"SELECT * FROM TableA WHERE ColA = 4 AND ColB = 5;",
columns=[column_1, column_2],
)
query_2 = Query(
18,
"SELECT * FROM TableA WHERE ColA = 3 AND ColC = 2;",
columns=[column_1, column_3],
)
database_name = "test_DB"
workload = Workload([query_1, query_2], database_name)
indexable_columns = workload.indexable_columns()
self.assertEqual(sorted(indexable_columns),
sorted([column_1, column_2, column_3]))
def setUp(self):
self.connector = MockConnector()
self.algo = DropHeuristicAlgorithm(database_connector=self.connector)
self.column_0 = Column("Col0")
self.column_1 = Column("Col1")
self.column_2 = Column("Col2")
self.all_columns = [self.column_0, self.column_1, self.column_2]
self.table = Table("TableA")
self.table.add_columns(self.all_columns)
self.index_0 = Index([self.column_0])
self.index_1 = Index([self.column_1])
self.index_2 = Index([self.column_2])
query_0 = Query(0, "SELECT * FROM TableA WHERE Col0 = 4;",
[self.column_0])
query_1 = Query(
1,
"SELECT * FROM TableA WHERE Col0 = 1 AND Col1 = 2 AND Col2 = 3;",
self.all_columns,
)
self.database_name = "test_DB"
self.workload = Workload([query_0, query_1])
self.algo.workload = self.workload
self.algo.cost_evaluation.calculate_cost = MagicMock(
side_effect=self._calculate_cost_mock)
def test_calculate_indexes_1MB_2column(self, get_utilized_indexes_mock):
algorithm = RelaxationAlgorithm(
database_connector=self.connector,
parameters={
"max_index_width": 2,
"budget_MB": 1
},
)
algorithm.cost_evaluation.cache = mock_cache
algorithm.cost_evaluation._prepare_cost_calculation = (
self.set_estimated_index_sizes)
algorithm.cost_evaluation.estimate_size = self.set_estimated_index_size
get_utilized_indexes_mock.return_value = (
{
Index([column_A_0], 1000 * 1000),
Index([column_A_0, column_A_1], 2000 * 1000),
},
None,
)
index_selection = algorithm.calculate_best_indexes(
Workload([query_0, query_1]))
# The single column index is dropped first, because of the lower penalty.
# The multi column index is prefixed second.
self.assertEqual(set(index_selection), {Index([column_A_0])})
def setUpClass(cls):
cls.db_name = "TestDB"
cls.table = Table("TestTableA")
cls.columns = [
Column("Col0"),
Column("Col1"),
Column("Col2"),
Column("Col3"),
Column("Col4"),
]
cls.table.add_columns(cls.columns)
cls.queries = [
Query(0, "SELECT * FROM TestTableA WHERE Col0 = 4",
[cls.columns[0]]),
Query(1, "SELECT * FROM TestTableA WHERE Col1 = 3",
[cls.columns[1]]),
Query(
2,
"SELECT * FROM TestTableA WHERE Col0 = 14 AND Col1 = 13",
[cls.columns[0], cls.columns[1]],
),
]
cls.workload = Workload(cls.queries, cls.db_name)
def test_calculate_indexes_1MB_2column(self):
algorithm = RelaxationAlgorithm(
database_connector=self.connector,
parameters={"max_index_columns": 2, "budget": 1},
)
algorithm.cost_evaluation.cache = mock_cache
algorithm.cost_evaluation._prepare_cost_calculation = (
self.set_estimated_index_sizes
)
algorithm.cost_evaluation.estimate_size = self.set_estimated_index_size
algorithm._exploit_virtual_indexes = lambda workload: (
None,
{
Index([column_A_0], 1000 * 1000),
Index([column_A_0, column_A_1], 2000 * 1000),
},
)
index_selection = algorithm.calculate_best_indexes(
Workload([query_0, query_1], self.database_name)
)
# The single column index is dropped first, because of the lower penalty.
# The multi column index is prefixed second.
self.assertEqual(set(index_selection), {Index([column_A_0])})
def test_calculate_indexes_3000MB_2column(self):
algorithm = RelaxationAlgorithm(
database_connector=self.connector,
parameters={"max_index_columns": 2, "budget": 3},
)
algorithm.cost_evaluation.cache = mock_cache
algorithm.cost_evaluation._prepare_cost_calculation = (
self.set_estimated_index_sizes
)
algorithm.cost_evaluation.estimate_size = self.set_estimated_index_size
algorithm._exploit_virtual_indexes = lambda workload: (
None,
{
Index([column_A_0], 1000 * 1000),
Index([column_A_0, column_A_1], 2000 * 1000),
},
)
index_selection = algorithm.calculate_best_indexes(
Workload([query_0, query_1], self.database_name)
)
self.assertEqual(
set(index_selection),
set([Index([column_A_0]), Index([column_A_0, column_A_1])]),
)
def setUp(self):
self.connector = MockConnector()
self.algo = EPICAlgorithm(database_connector=self.connector)
self.column_1 = Column("ColA")
self.column_2 = Column("ColB")
self.column_3 = Column("ColC")
self.all_columns = [self.column_1, self.column_2, self.column_3]
self.table = Table("TableA")
self.table.add_columns(self.all_columns)
self.index_1 = Index([self.column_1])
self.index_1.estimated_size = 5
self.index_2 = Index([self.column_2])
self.index_2.estimated_size = 1
self.index_3 = Index([self.column_3])
self.index_3.estimated_size = 3
query_1 = Query(0, "SELECT * FROM TableA WHERE ColA = 4;", [self.column_1])
query_2 = Query(
1,
"SELECT * FROM TableA WHERE ColA = 1 AND ColB = 2 AND ColC = 3;",
self.all_columns,
)
self.database_name = "test_DB"
self.workload = Workload([query_1, query_2], self.database_name)
self.algo.workload = self.workload
def test_calculate_indexes_3000MB_2column(self, get_utilized_indexes_mock):
algorithm = RelaxationAlgorithm(
database_connector=self.connector,
parameters={
"max_index_width": 2,
"budget_MB": 3
},
)
algorithm.cost_evaluation.cache = mock_cache
algorithm.cost_evaluation._prepare_cost_calculation = (
self.set_estimated_index_sizes)
algorithm.cost_evaluation.estimate_size = self.set_estimated_index_size
get_utilized_indexes_mock.return_value = (
{
Index([column_A_0], 1000 * 1000),
Index([column_A_0, column_A_1], 2000 * 1000),
},
None,
)
index_selection = algorithm.calculate_best_indexes(
Workload([query_0, query_1]))
self.assertEqual(
set(index_selection),
set([Index([column_A_0]),
Index([column_A_0, column_A_1])]),
)
def test_get_utilized_indexes(self):
class CostEvaluationMock:
def which_indexes_utilized_and_cost(_, query, indexes):
if query.nr == 0:
return [{self.index_0}, 17]
if query.nr == 1:
return [{self.index_0, self.index_2}, 14]
def calculate_cost(_, workload, indexes):
assert len(workload.queries) == 1, (
"get_utilized_indexes' calculate_cost_mock should not be "
"called with workloads that contain more than one query"
)
assert indexes == [], (
"get_utilized_indexes' calculate_cost_mock should not be "
"called with indexes"
)
query = workload.queries[0]
if query.nr == 0:
return 170
if query.nr == 1:
return 140
query_0 = Query(0, "SELECT * FROM tablea WHERE col0 = 4;", [self.column_a_0])
query_1 = Query(
1,
(
"SELECT * FROM tablea as a, tableb as b WHERE a.col0 = 4 AND "
"a.col1 = 17AND b.col0 = 3;"
),
[self.column_a_0, self.column_a_1, self.column_b_0],
)
workload = Workload([query_0, query_1])
candidates = candidates_per_query(workload, 2, syntactically_relevant_indexes)
utilized_indexes, query_details = get_utilized_indexes(
workload, candidates, CostEvaluationMock()
)
self.assertEqual(query_details, {})
self.assertEqual(utilized_indexes, {self.index_0, self.index_2})
expected_first_result = {
"cost_without_indexes": 170,
"cost_with_indexes": 17,
"utilized_indexes": {self.index_0},
}
expected_second_result = {
"cost_without_indexes": 140,
"cost_with_indexes": 14,
"utilized_indexes": {self.index_0, self.index_2},
}
utilized_indexes, query_details = get_utilized_indexes(
workload, candidates, CostEvaluationMock(), detailed_query_information=True
)
self.assertEqual(query_details[query_0], expected_first_result)
self.assertEqual(query_details[query_1], expected_second_result)
self.assertEqual(utilized_indexes, {self.index_0, self.index_2})
def test_workload(self):
query_1 = Query(17, "SELECT * FROM TableA;")
query_2 = Query(18, "SELECT * FROM nation;")
database_name = "test_DB"
workload = Workload([query_1, query_2], database_name)
self.assertEqual(workload.queries, [query_1, query_2])
self.assertEqual(workload.database_name, database_name)
def test_calculate_best_only_executable_once(self):
workload = Workload([])
selection_algorithm = NoIndexAlgorithm(
PostgresDatabaseConnector(None, autocommit=True))
self.assertFalse(selection_algorithm.did_run)
selection_algorithm.calculate_best_indexes(workload)
self.assertTrue(selection_algorithm.did_run)
with self.assertRaises(AssertionError):
selection_algorithm.calculate_best_indexes(workload)
def test_calculate_indexes_2indexes_2columns(self):
algorithm = AutoAdminAlgorithm(
database_connector=self.connector,
parameters={"max_indexes": 2, "max_index_width": 2},
)
algorithm.cost_evaluation.cache = mock_cache
algorithm.cost_evaluation._prepare_cost_calculation = (
lambda indexes, store_size=False: None
)
index_selection = algorithm.calculate_best_indexes(Workload([query_0, query_1]))
self.assertEqual(set(index_selection), set([Index([column_A_0, column_A_1])]))
def test_db2advis_algorithm(self):
parameters = {}
db2advis_algorithm = self.index_selection.create_algorithm_object(
"db2advis", parameters)
workload = Workload([self.small_tpch.queries[0]])
possible = candidates_per_query(
workload,
max_index_width=3,
candidate_generator=syntactically_relevant_indexes,
)[0]
indexes = db2advis_algorithm.calculate_best_indexes(workload)
self.assertTrue(len(possible) >= len(indexes))
def test_exploit_virtual_indexes(self):
def _simulate_index_mock(index, store_size):
index.hypopg_name = f"<1337>btree_{index.columns}"
# For some reason, the database decides to only use an index for one of
# the filters
def _simulate_get_plan(query):
if "Table0" in query.text:
return {
"Total Cost": 17,
"Plans": [{
"Index Name": "<1337>btree_(C table0.col1,)"
}],
}
return {
"Total Cost": 5,
"Plans": [{
"Simple Table Retrieve": "table1"
}]
}
query_0 = Query(
0,
"SELECT * FROM Table0 WHERE Col0 = 1 AND Col1 = 2;",
[self.column_0, self.column_1],
)
query_1 = Query(1, "SELECT * FROM Table1;", [])
workload = Workload([query_0, query_1], "database_name")
self.algo.database_connector.get_plan = MagicMock(
side_effect=_simulate_get_plan)
self.algo.what_if.simulate_index = MagicMock(
side_effect=_simulate_index_mock)
self.algo.what_if.drop_all_simulated_indexes = MagicMock()
query_results, index_candidates = self.algo._exploit_virtual_indexes(
workload)
self.assertEqual(len(query_results), len(workload.queries))
expected_first_result = {
"cost_without_indexes": 17,
"cost_with_recommended_indexes": 17,
"recommended_indexes": set([Index([self.column_1])]),
}
expected_second_result = {
"cost_without_indexes": 5,
"cost_with_recommended_indexes": 5,
"recommended_indexes": set(),
}
self.assertEqual(query_results[query_0], expected_first_result)
self.assertEqual(query_results[query_1], expected_second_result)
self.assertEqual(index_candidates, set([Index([self.column_1])]))
def test_cache_hit(self):
self.assertEqual(self.cost_evaluation.cost_requests, 0)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
workload = Workload([self.queries[0]])
self.cost_evaluation.calculate_cost(workload, indexes=set())
self.assertEqual(self.cost_evaluation.cost_requests, 1)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
self.assertEqual(self.connector.get_cost.call_count, 1)
self.cost_evaluation.calculate_cost(workload, indexes=set())
self.assertEqual(self.cost_evaluation.cost_requests, 2)
self.assertEqual(self.cost_evaluation.cache_hits, 1)
self.assertEqual(self.connector.get_cost.call_count, 1)
def test_cache_hit_different_index_same_columns(self):
self.assertEqual(self.cost_evaluation.cost_requests, 0)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
workload = Workload([self.queries[0]])
self.cost_evaluation.calculate_cost(workload, set([Index([self.columns[0]])]))
self.assertEqual(self.cost_evaluation.cost_requests, 1)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
self.assertEqual(self.connector.get_cost.call_count, 1)
self.cost_evaluation.calculate_cost(workload, set([Index([self.columns[0]])]))
self.assertEqual(self.cost_evaluation.cost_requests, 2)
self.assertEqual(self.cost_evaluation.cache_hits, 1)
self.assertEqual(self.connector.get_cost.call_count, 1)
def test_no_cache_hit_unseen(self):
self.assertEqual(self.cost_evaluation.cost_requests, 0)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
workload = Workload([self.queries[0]], self.db_name)
index_0 = Index([self.columns[0]])
self.cost_evaluation.calculate_cost(workload, indexes=set())
self.assertEqual(self.cost_evaluation.cost_requests, 1)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
self.assertEqual(self.connector.get_cost.call_count, 1)
self.cost_evaluation.calculate_cost(workload, set([index_0]))
self.assertEqual(self.cost_evaluation.cost_requests, 2)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
self.assertEqual(self.connector.get_cost.call_count, 2)
self.connector.simulate_index.assert_called_with(index_0)
def test_cache_hit_non_relevant_index(self):
self.assertEqual(self.cost_evaluation.cost_requests, 0)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
workload = Workload([self.queries[0]])
index_1 = Index([self.columns[1]])
self.cost_evaluation.calculate_cost(workload, indexes=set())
self.assertEqual(self.cost_evaluation.cost_requests, 1)
self.assertEqual(self.cost_evaluation.cache_hits, 0)
self.assertEqual(self.connector.get_cost.call_count, 1)
self.cost_evaluation.calculate_cost(workload, set([index_1]))
self.assertEqual(self.cost_evaluation.cost_requests, 2)
self.assertEqual(self.cost_evaluation.cache_hits, 1)
self.assertEqual(self.connector.get_cost.call_count, 1)
self.connector.simulate_index.assert_called_with(index_1)
def setUpClass(cls):
cls.db_name = "tpch_test_db_database"
cls.scale_factor = 0.001
generating_connector = PostgresDatabaseConnector(None, autocommit=True)
table_generator = TableGenerator(
"tpch",
cls.scale_factor,
generating_connector,
explicit_database_name=cls.db_name,
)
cls.db = PostgresDatabaseConnector(cls.db_name)
query_generator = QueryGenerator("tpch", cls.scale_factor, cls.db,
[5, 6], table_generator.columns)
cls.workload = Workload(query_generator.queries)
generating_connector.close()
def test_candidates_per_query(self):
MAX_INDEX_WIDTH = 2
query_1 = Query(18, """SELECT * FROM 1;""")
workload = Workload([self.query_0, query_1])
syntactically_relevant_indexes_mock = MagicMock(
return_value=syntactically_relevant_indexes)
result = candidates_per_query(
workload,
max_index_width=MAX_INDEX_WIDTH,
candidate_generator=syntactically_relevant_indexes_mock,
)
self.assertEqual(len(result), len(workload.queries))
syntactically_relevant_indexes_mock.assert_called_with(
query_1, MAX_INDEX_WIDTH)
syntactically_relevant_indexes_mock.assert_any_call(
self.query_0, MAX_INDEX_WIDTH)
def test_calculate_best_indexes_scenario_3(self):
query_1 = Query(
0,
"SELECT * FROM TableA WHERE ColA = 1 AND ColB = 2;",
[self.column_1, self.column_2],
)
workload = Workload([query_1])
self.algo.cost_evaluation.calculate_cost = MagicMock(
side_effect=self._calculate_cost_mock_3)
# Budget too small for multi
self.algo.budget = 2
indexes = self.algo._calculate_best_indexes(workload)
expected_indexes = [Index([self.column_2])]
self.assertEqual(indexes, expected_indexes)
# Picks multi with best ratio
self.algo.budget = 4
indexes = self.algo._calculate_best_indexes(workload)
expected_indexes = [Index([self.column_2, self.column_1])]
self.assertEqual(indexes, expected_indexes)
def test_calculate_best(self):
workload = Workload([], self.db_name)
with self.assertRaises(NotImplementedError):
self.selection_algorithm.calculate_best_indexes(workload)
def test_cost_eval_cost_empty_workload(self):
workload = Workload([], self.db_name)
cost_eval = self.selection_algorithm.cost_evaluation
cost = cost_eval.calculate_cost(workload, [])
self.assertEqual(cost, 0)
def test_workload(self):
query_1 = Query(17, "SELECT * FROM TableA;")
query_2 = Query(18, "SELECT * FROM nation;")
workload = Workload([query_1, query_2])
self.assertEqual(workload.queries, [query_1, query_2])
