planner: fix index join range display when executing the cached plan

planner/core/exhaust_physical_plans.go

@@ -1598,7 +1598,10 @@ func (ijHelper *indexJoinBuildHelper) analyzeLookUpFilters(path *util.AccessPath
 func (ijHelper *indexJoinBuildHelper) updateBestChoice(ranges ranger.MutableRanges, path *util.AccessPath, accesses,
 	remained []expression.Expression, lastColManager *ColWithCmpFuncManager, usedColsLen int, rebuildMode bool) {
 	if rebuildMode { // rebuild the range for plan-cache, update the chosenRanges anyway
+		ijHelper.chosenPath = path
 		ijHelper.chosenRanges = ranges
+		ijHelper.chosenAccess = accesses
+		ijHelper.idxOff2KeyOff = ijHelper.curIdxOff2KeyOff
 		return
 	}
 

planner/core/integration_test.go

@@ -7652,8 +7652,7 @@ func TestPlanCacheForIndexJoinRangeFallback(t *testing.T) {
 	tk.Session().SetSessionManager(&testkit.MockSessionManager{PS: ps})
 	rows = tk.MustQuery(fmt.Sprintf("explain for connection %d", tkProcess.ID)).Rows()
 	// We don't limit range mem usage when rebuilding index join ranges for the cached plan. So [? aaaaaa,? aaaaaa], [? bbbbbb,? bbbbbb], [? cccccc,? cccccc] can be built.
-	// TODO: use the right range `range: decided by [eq(test.t1.a, test.t2.d) in(test.t1.b, aaaaaa, bbbbbb, cccccc)]` after https://github.com/pingcap/tidb/issues/38269 is fixed.
-	require.True(t, strings.Contains(rows[6][4].(string), "range: decided by [eq(test.t1.a, test.t2.d) in(test.t1.b, a, b, c)]"))
+	require.True(t, strings.Contains(rows[6][4].(string), "range: decided by [eq(test.t1.a, test.t2.d) in(test.t1.b, aaaaaa, bbbbbb, cccccc)]"))
 
 	// Test the plan with range fallback would not be put into cache.
 	tk.MustExec("prepare stmt2 from 'select /*+ inl_join(t1) */ * from  t1 join t2 on t1.a = t2.d where t1.b in (?, ?, ?, ?, ?)'")

planner/core/plan_cache.go

@@ -305,6 +305,26 @@ func RebuildPlan4CachedPlan(p Plan) error {
 	return rebuildRange(p)
 }
 
+func updateRange(p PhysicalPlan, ranges ranger.Ranges, rangeInfo string) error {
+	switch x := p.(type) {
+	case *PhysicalTableScan:
+		x.Ranges = ranges
+		x.rangeInfo = rangeInfo
+		return nil
+	case *PhysicalIndexScan:
+		x.Ranges = ranges
+		x.rangeInfo = rangeInfo
+		return nil
+	case *PhysicalTableReader:
+		return updateRange(x.TablePlans[0], ranges, rangeInfo)
+	case *PhysicalIndexReader:
+		return updateRange(x.IndexPlans[0], ranges, rangeInfo)
+	case *PhysicalIndexLookUpReader:
+		return updateRange(x.IndexPlans[0], ranges, rangeInfo)
+	}
+	return nil
+}
+
 // rebuildRange doesn't set mem limit for building ranges. There are two reasons why we don't restrict range mem usage here.
 //  1. The cached plan must be able to build complete ranges under mem limit when it is generated. Hence we can just build
 //     ranges from x.AccessConditions. The only difference between the last ranges and new ranges is the change of parameter
@@ -327,6 +347,15 @@ func rebuildRange(p Plan) error {
 		if err := x.Ranges.Rebuild(); err != nil {
 			return err
 		}
+		if mutableRange, ok := x.Ranges.(*mutableIndexJoinRange); ok {
+			helper := mutableRange.buildHelper
+			rangeInfo := helper.buildRangeDecidedByInformation(helper.chosenPath.IdxCols, mutableRange.outerJoinKeys)
+			innerPlan := x.Children()[x.InnerChildIdx]
+			err = updateRange(innerPlan, x.Ranges.Range(), rangeInfo)
+			if err != nil {
+				return err
+			}
+		}
 		for _, child := range x.Children() {
 			err = rebuildRange(child)
 			if err != nil {

planner/core/plan_cache_test.go

@@ -27,6 +27,7 @@ import (
 	plannercore "github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/testkit"
 	"github.com/pingcap/tidb/types"
+	"github.com/pingcap/tidb/util"
 	"github.com/stretchr/testify/require"
 )
 
@@ -110,3 +111,22 @@ func TestGeneralPlanCacheBasically(t *testing.T) {
 		tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1")) // this plan is from plan-cache
 	}
 }
+
+func TestIssue38269(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec(`set @@tidb_enable_prepared_plan_cache=1`)
+	tk.MustExec("set @@tidb_enable_collect_execution_info=0")
+	tk.MustExec("use test")
+	tk.MustExec("create table t1(a int)")
+	tk.MustExec("create table t2(a int, b int, c int, index idx(a, b))")
+	tk.MustExec("prepare stmt1 from 'select /*+ inl_join(t2) */ * from t1 join t2 on t1.a = t2.a where t2.b in (?, ?, ?)'")
+	tk.MustExec("set @a = 10, @b = 20, @c = 30, @d = 40, @e = 50, @f = 60")
+	tk.MustExec("execute stmt1 using @a, @b, @c")
+	tk.MustExec("execute stmt1 using @d, @e, @f")
+	tkProcess := tk.Session().ShowProcess()
+	ps := []*util.ProcessInfo{tkProcess}
+	tk.Session().SetSessionManager(&testkit.MockSessionManager{PS: ps})
+	rows := tk.MustQuery(fmt.Sprintf("explain for connection %d", tkProcess.ID)).Rows()
+	require.Contains(t, rows[6][4], "range: decided by [eq(test.t2.a, test.t1.a) in(test.t2.b, 40, 50, 60)]")
+}