planner: remove the limit that nth_plan hint value can't exceed 100 (…

…pingcap#19037)
m4ver1k · Aug 10, 2020 · 8978773 · 8978773
1 parent b8670fb
commit 8978773
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Showing 3 changed files with 8 additions and 8 deletions.
diff --git a/planner/core/find_best_task.go b/planner/core/find_best_task.go
@@ -62,17 +62,17 @@ var aggFuncFactor = map[string]float64{
 }
 
 // PlanCounterTp is used in hint nth_plan() to indicate which plan to use.
-type PlanCounterTp int8
+type PlanCounterTp int64
 
 // PlanCounterDisabled is the default value of PlanCounterTp, indicating that optimizer needn't force a plan.
 var PlanCounterDisabled PlanCounterTp = -1
 
 // Dec minus PlanCounterTp value by x.
-func (c *PlanCounterTp) Dec(x int8) {
+func (c *PlanCounterTp) Dec(x int64) {
 	if *c <= 0 {
 		return
 	}
-	*c = PlanCounterTp(int8(*c) - x)
+	*c = PlanCounterTp(int64(*c) - x)
 	if *c < 0 {
 		*c = 0
 	}
@@ -260,7 +260,7 @@ func (p *baseLogicalPlan) enumeratePhysicalPlans4Task(physicalPlans []PhysicalPl
 		}
 
 		cntPlan += curCntPlan
-		planCounter.Dec(int8(curCntPlan))
+		planCounter.Dec(curCntPlan)
 
 		if planCounter.Empty() {
 			bestTask = curTask

diff --git a/planner/core/plan_test.go b/planner/core/plan_test.go
@@ -266,6 +266,10 @@ func (s *testPlanNormalize) TestNthPlanHint(c *C) {
 	tk.MustQuery("show warnings").Check(testkit.Rows(
 		"Warning 1105 The parameter of nth_plan() is out of range."))
 
+	tk.MustExec("explain format='hint' select /*+ nth_plan(500) */ * from t where a=1 and b=1")
+	tk.MustQuery("show warnings").Check(testkit.Rows(
+		"Warning 1105 The parameter of nth_plan() is out of range."))
+
 	// Test warning for multiply hints.
 	tk.MustQuery("explain format='hint' select /*+ nth_plan(1) nth_plan(2) */ * from t where a=1 and b=1").Check(testkit.Rows(
 		"use_index(@`sel_1` `test`.`t` `a_2`), nth_plan(1), nth_plan(2)"))

diff --git a/planner/optimize.go b/planner/optimize.go
@@ -470,10 +470,6 @@ func handleStmtHints(hints []*ast.TableOptimizerHint) (stmtHints stmtctx.StmtHin
 			stmtHints.ForceNthPlan = -1
 			warn := errors.Errorf("the hintdata for NTH_PLAN() is too small, hint ignored.")
 			warns = append(warns, warn)
-		} else if stmtHints.ForceNthPlan > 100 {
-			stmtHints.ForceNthPlan = -1
-			warn := errors.Errorf("the hintdata for NTH_PLAN() is too big, hint ignored.")
-			warns = append(warns, warn)
 		}
 	} else {
 		stmtHints.ForceNthPlan = -1