// Copyright 2018 PingCAP, Inc. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // See the License for the specific language governing permissions and // limitations under the License. package cascades import ( "context" "math" "testing" . "github.com/pingcap/check" "github.com/pingcap/parser" "github.com/pingcap/parser/model" "github.com/pingcap/tidb/expression" "github.com/pingcap/tidb/infoschema" plannercore "github.com/pingcap/tidb/planner/core" "github.com/pingcap/tidb/planner/memo" "github.com/pingcap/tidb/planner/property" "github.com/pingcap/tidb/sessionctx" "github.com/pingcap/tidb/util/testleak" ) func TestT(t *testing.T) { CustomVerboseFlag = true TestingT(t) } var _ = Suite(&testCascadesSuite{}) type testCascadesSuite struct { *parser.Parser is infoschema.InfoSchema sctx sessionctx.Context optimizer *Optimizer } func (s *testCascadesSuite) SetUpSuite(c *C) { testleak.BeforeTest() s.is = infoschema.MockInfoSchema([]*model.TableInfo{plannercore.MockSignedTable()}) s.sctx = plannercore.MockContext() s.Parser = parser.New() s.optimizer = NewOptimizer() } func (s *testCascadesSuite) TearDownSuite(c *C) { testleak.AfterTest(c)() } func (s *testCascadesSuite) TestImplGroupZeroCost(c *C) { stmt, err := s.ParseOneStmt("select t1.a, t2.a from t as t1 left join t as t2 on t1.a = t2.a where t1.a < 1.0", "", "") c.Assert(err, IsNil) p, _, err := plannercore.BuildLogicalPlan(context.Background(), s.sctx, stmt, s.is) c.Assert(err, IsNil) logic, ok := p.(plannercore.LogicalPlan) c.Assert(ok, IsTrue) rootGroup := memo.Convert2Group(logic) prop := &property.PhysicalProperty{ ExpectedCnt: math.MaxFloat64, } impl, err := s.optimizer.implGroup(rootGroup, prop, 0.0) c.Assert(impl, IsNil) c.Assert(err, IsNil) } func (s *testCascadesSuite) TestInitGroupSchema(c *C) { stmt, err := s.ParseOneStmt("select a from t", "", "") c.Assert(err, IsNil) p, _, err := plannercore.BuildLogicalPlan(context.Background(), s.sctx, stmt, s.is) c.Assert(err, IsNil) logic, ok := p.(plannercore.LogicalPlan) c.Assert(ok, IsTrue) g := memo.Convert2Group(logic) c.Assert(g, NotNil) c.Assert(g.Prop, NotNil) c.Assert(g.Prop.Schema.Len(), Equals, 1) c.Assert(g.Prop.Stats, IsNil) } func (s *testCascadesSuite) TestFillGroupStats(c *C) { stmt, err := s.ParseOneStmt("select * from t t1 join t t2 on t1.a = t2.a", "", "") c.Assert(err, IsNil) p, _, err := plannercore.BuildLogicalPlan(context.Background(), s.sctx, stmt, s.is) c.Assert(err, IsNil) logic, ok := p.(plannercore.LogicalPlan) c.Assert(ok, IsTrue) rootGroup := memo.Convert2Group(logic) err = s.optimizer.fillGroupStats(rootGroup) c.Assert(err, IsNil) c.Assert(rootGroup.Prop.Stats, NotNil) } func (s *testCascadesSuite) TestPreparePossibleProperties(c *C) { s.optimizer.ResetTransformationRules(map[memo.Operand][]Transformation{ memo.OperandDataSource: { NewRuleEnumeratePaths(), }, }) defer func() { s.optimizer.ResetTransformationRules(DefaultRuleBatches...) }() stmt, err := s.ParseOneStmt("select f, sum(a) from t group by f", "", "") c.Assert(err, IsNil) p, _, err := plannercore.BuildLogicalPlan(context.Background(), s.sctx, stmt, s.is) c.Assert(err, IsNil) logic, ok := p.(plannercore.LogicalPlan) c.Assert(ok, IsTrue) logic, err = s.optimizer.onPhasePreprocessing(s.sctx, logic) c.Assert(err, IsNil) // collect the target columns: f, a ds, ok := logic.Children()[0].Children()[0].(*plannercore.DataSource) c.Assert(ok, IsTrue) var columnF, columnA *expression.Column for i, col := range ds.Columns { if col.Name.L == "f" { columnF = ds.Schema().Columns[i] } else if col.Name.L == "a" { columnA = ds.Schema().Columns[i] } } c.Assert(columnF, NotNil) c.Assert(columnA, NotNil) agg, ok := logic.Children()[0].(*plannercore.LogicalAggregation) c.Assert(ok, IsTrue) group := memo.Convert2Group(agg) err = s.optimizer.onPhaseExploration(s.sctx, group) c.Assert(err, IsNil) // The memo looks like this: // Group#0 Schema:[Column#13,test.t.f] // Aggregation_2 input:[Group#1], group by:test.t.f, funcs:sum(test.t.a), firstrow(test.t.f) // Group#1 Schema:[test.t.a,test.t.f] // TiKVSingleGather_5 input:[Group#2], table:t // TiKVSingleGather_9 input:[Group#3], table:t, index:f_g // TiKVSingleGather_7 input:[Group#4], table:t, index:f // Group#2 Schema:[test.t.a,test.t.f] // TableScan_4 table:t, pk col:test.t.a // Group#3 Schema:[test.t.a,test.t.f] // IndexScan_8 table:t, index:f, g // Group#4 Schema:[test.t.a,test.t.f] // IndexScan_6 table:t, index:f propMap := make(map[*memo.Group][][]*expression.Column) aggProp := preparePossibleProperties(group, propMap) // We only have one prop for Group0 : f c.Assert(len(aggProp), Equals, 1) c.Assert(aggProp[0][0].Equal(nil, columnF), IsTrue) gatherGroup := group.Equivalents.Front().Value.(*memo.GroupExpr).Children[0] gatherProp, ok := propMap[gatherGroup] c.Assert(ok, IsTrue) // We have 2 props for Group1: [f], [a] c.Assert(len(gatherProp), Equals, 2) for _, prop := range gatherProp { c.Assert(len(prop), Equals, 1) c.Assert(prop[0].Equal(nil, columnA) || prop[0].Equal(nil, columnF), IsTrue) } } // fakeTransformation is used for TestAppliedRuleSet. type fakeTransformation struct { baseRule appliedTimes int } // OnTransform implements Transformation interface. func (rule *fakeTransformation) OnTransform(old *memo.ExprIter) (newExprs []*memo.GroupExpr, eraseOld bool, eraseAll bool, err error) { rule.appliedTimes++ old.GetExpr().AddAppliedRule(rule) return []*memo.GroupExpr{old.GetExpr()}, true, false, nil } func (s *testCascadesSuite) TestAppliedRuleSet(c *C) { rule := fakeTransformation{} rule.pattern = memo.NewPattern(memo.OperandProjection, memo.EngineAll) s.optimizer.ResetTransformationRules(map[memo.Operand][]Transformation{ memo.OperandProjection: { &rule, }, }) defer func() { s.optimizer.ResetTransformationRules(DefaultRuleBatches...) }() stmt, err := s.ParseOneStmt("select 1", "", "") c.Assert(err, IsNil) p, _, err := plannercore.BuildLogicalPlan(context.Background(), s.sctx, stmt, s.is) c.Assert(err, IsNil) logic, ok := p.(plannercore.LogicalPlan) c.Assert(ok, IsTrue) group := memo.Convert2Group(logic) err = s.optimizer.onPhaseExploration(s.sctx, group) c.Assert(err, IsNil) c.Assert(rule.appliedTimes, Equals, 1) }