planner: fix planner can't error for union-all query when new-only-fu…

…ll-group-check is enabled (pingcap#59212)

close pingcap#59211

pkg/planner/core/operator/logicalop/logical_projection.go

@@ -407,6 +407,10 @@ func (p *LogicalProjection) ExtractFD() *fd.FDSet {
 	for idx, expr := range p.Exprs {
 		switch x := expr.(type) {
 		case *expression.Column:
+			//  column projected as a new column again.
+			if int(x.UniqueID) != outputColsUniqueIDsArray[idx] {
+				fds.AddEquivalence(intset.NewFastIntSet(int(x.UniqueID)), intset.NewFastIntSet(outputColsUniqueIDsArray[idx]))
+			}
 			continue
 		case *expression.CorrelatedColumn:
 			// t1(a,b,c), t2(m,n)

pkg/planner/core/operator/logicalop/logical_union_all.go

@@ -19,11 +19,13 @@ import (
 
 	"github.com/pingcap/tidb/pkg/expression"
 	"github.com/pingcap/tidb/pkg/planner/core/base"
+	fd "github.com/pingcap/tidb/pkg/planner/funcdep"
 	"github.com/pingcap/tidb/pkg/planner/property"
 	"github.com/pingcap/tidb/pkg/planner/util"
 	"github.com/pingcap/tidb/pkg/planner/util/optimizetrace"
 	"github.com/pingcap/tidb/pkg/planner/util/optimizetrace/logicaltrace"
 	"github.com/pingcap/tidb/pkg/planner/util/utilfuncp"
+	"github.com/pingcap/tidb/pkg/util/intset"
 	"github.com/pingcap/tidb/pkg/util/plancodec"
 )
 
@@ -191,7 +193,32 @@ func (p *LogicalUnionAll) ExhaustPhysicalPlans(prop *property.PhysicalProperty)
 
 // CanPushToCop inherits BaseLogicalPlan.LogicalPlan.<21st> implementation.
 
-// ExtractFD inherits BaseLogicalPlan.LogicalPlan.<22nd> implementation.
+// ExtractFD implement base.LogicalPlan.<22nd> interface.
+func (p *LogicalUnionAll) ExtractFD() *fd.FDSet {
+	// basically extract the children's fdSet.
+	childFDs := make([]*fd.FDSet, 0, len(p.children))
+	for _, child := range p.children {
+		childFD := child.ExtractFD()
+		childFDs = append(childFDs, childFD)
+	}
+	// check the output columns' not-null property.
+	res := &fd.FDSet{}
+	notNullCols := intset.NewFastIntSet()
+	for _, col := range p.Schema().Columns {
+		notNullCols.Insert(int(col.UniqueID))
+	}
+	for _, childFD := range childFDs {
+		notNullCols.IntersectionWith(childFD.NotNullCols)
+	}
+	res.MakeNotNull(notNullCols)
+	// check the equivalency between children.
+	equivs := fd.FindCommonEquivClasses(childFDs)
+	for _, equiv := range equivs {
+		res.AddEquivalenceUnion(equiv)
+	}
+	p.fdSet = res
+	return res
+}
 
 // GetBaseLogicalPlan inherits BaseLogicalPlan.LogicalPlan.<23rd> implementation.
 

pkg/planner/core/stringer.go

@@ -75,6 +75,8 @@ func fdToString(in base.LogicalPlan, strs []string, idxs []int) ([]string, []int
 		strs = append(strs, "{"+x.FDs().String()+"}")
 	case *logicalop.LogicalJoin:
 		strs = append(strs, "{"+x.FDs().String()+"}")
+	case *logicalop.LogicalUnionAll:
+		strs = append(strs, "{"+x.FDs().String()+"}")
 	default:
 	}
 	return strs, idxs

pkg/planner/funcdep/extract_fd_test.go

@@ -238,7 +238,7 @@ func TestFDSet_ExtractFD(t *testing.T) {
 	}
 }
 
-func TestFDSet_ExtractFDForApply(t *testing.T) {
+func TestFDSet_ExtractFDForApplyAndUnion(t *testing.T) {
 	store := testkit.CreateMockStore(t)
 	par := parser.New()
 	par.SetParserConfig(parser.ParserConfig{EnableWindowFunction: true, EnableStrictDoubleTypeCheck: true})
@@ -249,6 +249,8 @@ func TestFDSet_ExtractFDForApply(t *testing.T) {
 	tk.MustExec("CREATE TABLE X (a INT PRIMARY KEY, b INT, c INT, d INT, e INT)")
 	tk.MustExec("CREATE UNIQUE INDEX uni ON X (b, c)")
 	tk.MustExec("CREATE TABLE Y (m INT, n INT, p INT, q INT, PRIMARY KEY (m, n))")
+	tk.MustExec("create table t1 (a int not null, b int, c int)")
+	tk.MustExec("create table t2 (e int not null, f int, g int)")
 
 	tests := []struct {
 		sql  string
@@ -308,6 +310,16 @@ func TestFDSet_ExtractFDForApply(t *testing.T) {
 			// p=1 is semi join's right condition which should **NOT** be conserved.
 			fd: "{(1)-->(2-5), (2,3)~~>(1,4,5)} >>> {(1)-->(2-5), (2,3)~~>(1,4,5)}",
 		},
+		{
+			sql:  "select * from t1 union all select * from t2",
+			best: "UnionAll{DataScan(t1)->Projection->DataScan(t2)->Projection}",
+			fd:   "{}",
+		},
+		{
+			sql:  "select * from t1 where a=b union all select * from t2 where e=f",
+			best: "UnionAll{DataScan(t1)->Projection->DataScan(t2)->Projection}",
+			fd:   "{(9,10)==(9,10)}",
+		},
 	}
 
 	ctx := context.TODO()

pkg/planner/funcdep/fd_graph.go

@@ -381,6 +381,10 @@ func (s *FDSet) addEquivalence(eqs intset.FastIntSet) {
 		// {} --> {a} + {a,b,c} --> {a,b,c} leading to extension {} --> {a,b,c}
 		s.AddConstants(eqClosure)
 	}
+	// the new equiv closure should share the same not-null attribute with the existed ones.
+	if s.NotNullCols.Intersects(eqClosure) {
+		s.MakeNotNull(eqClosure)
+	}
 }
 
 // AddEquivalence take two column id as parameters, establish a strict equivalence between
@@ -402,6 +406,12 @@ func (s *FDSet) AddEquivalence(from, to intset.FastIntSet) {
 	s.addEquivalence(from.Union(to))
 }
 
+// AddEquivalenceUnion add an equivalence union to fdSet.
+func (s *FDSet) AddEquivalenceUnion(union intset.FastIntSet) {
+	// no check for trivial equivalence, since it's a union of multiple equivalent columns.
+	s.addEquivalence(union)
+}
+
 // AddConstants adds a strict FD to the source which indicates that each of the given column
 // have the same constant value for all rows, or same null value for all rows if it's nullable.
 //
@@ -1173,7 +1183,6 @@ func (s *FDSet) makeEquivMap(detCols, projectedCols intset.FastIntSet) map[int]i
 // String returns format string of this FDSet.
 func (s *FDSet) String() string {
 	var builder strings.Builder
-
 	for i := range s.fdEdges {
 		if i != 0 {
 			builder.WriteString(", ")

tests/integrationtest/r/planner/funcdep/only_full_group_by.result

@@ -211,3 +211,12 @@ drop table if exists t1;
 create table t1(a int not null, b int not null, index(a));
 select b from t1 group by a;
 Error 1055 (42000): Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'planner__funcdep__only_full_group_by.t1.b' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
+drop table if exists t;
+create table t (a int, b int, c int);
+insert into t values (1, 2, 3);
+select a,max(b) as max_b from (select * from t union all select * from t) x ;
+Error 8123 (HY000): In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'x.a'; this is incompatible with sql_mode=only_full_group_by
+select a,max(b) as max_b from (select * from t union all select 1,2,3 ) x ;
+Error 8123 (HY000): In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'x.a'; this is incompatible with sql_mode=only_full_group_by
+select a,max(b) as max_b from (select * from t where a=1 union all select 1,2,3 ) x ;
+Error 8123 (HY000): In aggregated query without GROUP BY, expression #1 of SELECT list contains nonaggregated column 'x.a'; this is incompatible with sql_mode=only_full_group_by

tests/integrationtest/t/planner/funcdep/only_full_group_by.test

@@ -157,3 +157,13 @@ create table t1(a int not null, b int not null, index(a));
 -- error 1055
 select b from t1 group by a;
 
+# TestIssue59211
+drop table if exists t;
+create table t (a int, b int, c int);
+insert into t values (1, 2, 3);
+-- error 8123
+select a,max(b) as max_b from (select * from t union all select * from t) x ;
+-- error 8123
+select a,max(b) as max_b from (select * from t union all select 1,2,3 ) x ;
+-- error 8123
+select a,max(b) as max_b from (select * from t where a=1 union all select 1,2,3 ) x ;