plan: refine build plan and skip privilege check for foreign key cascade

executor/fktest/BUILD.bazel

@@ -12,9 +12,11 @@ go_test(
     deps = [
         "//config",
         "//executor",
+        "//infoschema",
         "//kv",
         "//meta/autoid",
         "//parser/ast",
+        "//parser/auth",
         "//parser/format",
         "//parser/model",
         "//parser/mysql",

executor/fktest/foreign_key_test.go

@@ -24,9 +24,12 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/executor"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/parser/ast"
+	"github.com/pingcap/tidb/parser/auth"
 	"github.com/pingcap/tidb/parser/format"
 	"github.com/pingcap/tidb/parser/model"
 	"github.com/pingcap/tidb/parser/mysql"
@@ -2167,7 +2170,7 @@ func TestExplainAnalyzeDMLWithFKInfo(t *testing.T) {
 				"├─Point_Get_.*" +
 				"└─Foreign_Key_Cascade_.* 0 root table:t2 total:.*, foreign_keys:1 foreign_key:fk, on_update:CASCADE N/A N/A.*" +
 				"  └─Update_.*" +
-				"    ├─Batch_Point_Get_.*" +
+				"    ├─Point_Get_.*" +
 				"    └─Foreign_Key_Check_.*",
 		},
 		{
@@ -2180,7 +2183,7 @@ func TestExplainAnalyzeDMLWithFKInfo(t *testing.T) {
 			plan: "Insert_.*" +
 				"└─Foreign_Key_Cascade_.* 0 root table:t2 total:.*, foreign_keys:1 foreign_key:fk, on_update:CASCADE N/A N/A.*" +
 				"  └─Update_.*" +
-				"    ├─Batch_Point_Get_.*" +
+				"    ├─Point_Get_.*" +
 				"    └─Foreign_Key_Check_.* 0 root table:t1 total:.*, check:.*, lock:.*, foreign_keys:1 foreign_key:fk, check_exist N/A N/A",
 		},
 		// Test foreign key use index.
@@ -2201,7 +2204,8 @@ func TestExplainAnalyzeDMLWithFKInfo(t *testing.T) {
 		},
 		{
 			sql: "explain analyze delete from t3 where id in (2,3)",
-			plan: "Delete_.*├─Batch_Point_Get_.*" +
+			plan: "Delete_.*" +
+				"├─Batch_Point_Get_.*" +
 				"└─Foreign_Key_Check_.* 0 root table:t4, index:idx_id total:.*, check:.*, foreign_keys:2 foreign_key:fk, check_not_exist N/A N/A",
 		},
 		{
@@ -2429,3 +2433,90 @@ func TestForeignKeyRuntimeStats(t *testing.T) {
 	cascadeStats.Merge(cascadeStats.Clone())
 	require.Equal(t, "total:2s, foreign_keys:20", cascadeStats.String())
 }
+
+func TestPrivilegeCheckInForeignKeyCascade(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.tidb_enable_foreign_key=1")
+	tk.MustExec("set @@foreign_key_checks=1")
+	tk.MustExec("use test")
+	tk.MustExec("create table t1 (id int key);")
+	tk.MustExec("create table t2 (id int key, foreign key fk (id) references t1(id) ON DELETE CASCADE ON UPDATE CASCADE);")
+	tk.MustExec("insert into t1 values (1), (2), (3);")
+	cases := []struct {
+		prepares []string
+		sql      string
+		err      error
+		t1Rows   []string
+		t2Rows   []string
+	}{
+		{
+			prepares: []string{"grant insert on test.t2 to 'u1'@'%';"},
+			sql:      "insert into t2 values (1), (2), (3);",
+			t1Rows:   []string{"1", "2", "3"},
+			t2Rows:   []string{"1", "2", "3"},
+		},
+		{
+			prepares: []string{"grant select, delete on test.t1 to 'u1'@'%';"},
+			sql:      "delete from t1 where id=1;",
+			t1Rows:   []string{"2", "3"},
+			t2Rows:   []string{"2", "3"},
+		},
+		{
+			prepares: []string{"grant select, update on test.t1 to 'u1'@'%';"},
+			sql:      "update t1 set id=id+10 where id=2;",
+			t1Rows:   []string{"3", "12"},
+			t2Rows:   []string{"3", "12"},
+		},
+	}
+	tk2 := testkit.NewTestKit(t, store)
+	tk2.MustExec("use test")
+	tk2.MustExec("set @@foreign_key_checks=1")
+	for _, ca := range cases {
+		tk.MustExec("drop user if exists 'u1'@'%'")
+		tk.MustExec("create user 'u1'@'%' identified by '';")
+		for _, sql := range ca.prepares {
+			tk.MustExec(sql)
+		}
+		err := tk2.Session().Auth(&auth.UserIdentity{Username: "u1", Hostname: "localhost", CurrentUser: true, AuthUsername: "u1", AuthHostname: "%"}, nil, []byte("012345678901234567890"))
+		require.NoError(t, err)
+		if ca.err == nil {
+			tk2.MustExec(ca.sql)
+		} else {
+			err = tk2.ExecToErr(ca.sql)
+			require.Error(t, err)
+		}
+		tk.MustQuery("select * from t1 order by id").Check(testkit.Rows(ca.t1Rows...))
+		tk.MustQuery("select * from t2 order by id").Check(testkit.Rows(ca.t2Rows...))
+	}
+}
+
+func TestTableLockInForeignKeyCascade(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.tidb_enable_foreign_key=1")
+	tk.MustExec("set @@foreign_key_checks=1")
+	tk.MustExec("use test")
+	tk2 := testkit.NewTestKit(t, store)
+	tk2.MustExec("use test")
+	tk2.MustExec("set @@foreign_key_checks=1")
+	// enable table lock
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.EnableTableLock = true
+	})
+	defer func() {
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.EnableTableLock = false
+		})
+	}()
+	tk.MustExec("create table t1 (id int key);")
+	tk.MustExec("create table t2 (id int key, foreign key fk (id) references t1(id) ON DELETE CASCADE ON UPDATE CASCADE);")
+	tk.MustExec("insert into t1 values (1), (2), (3);")
+	tk.MustExec("insert into t2 values (1), (2), (3);")
+	tk.MustExec("lock table t2 read;")
+	tk2.MustGetDBError("delete from t1 where id = 1", infoschema.ErrTableLocked)
+	tk.MustExec("unlock tables;")
+	tk2.MustExec("delete from t1 where id = 1")
+	tk.MustQuery("select * from t1 order by id").Check(testkit.Rows("2", "3"))
+	tk.MustQuery("select * from t2 order by id").Check(testkit.Rows("2", "3"))
+}

executor/foreign_key.go

@@ -732,7 +732,7 @@ func (fkc *FKCascadeExec) buildFKCascadePlan(ctx context.Context) (plannercore.P
 	if err != nil {
 		return nil, err
 	}
-	finalPlan, _, err := planner.Optimize(ctx, sctx, stmtNode, fkc.b.is)
+	finalPlan, err := planner.OptimizeForForeignKeyCascade(ctx, sctx, stmtNode, fkc.b.is)
 	if err != nil {
 		return nil, err
 	}

planner/core/point_get_plan.go

@@ -533,10 +533,8 @@ func TryFastPlan(ctx sessionctx.Context, node ast.Node) (p Plan) {
 		return nil
 	}
 
-	if !ctx.GetSessionVars().StmtCtx.InHandleForeignKeyTrigger {
-		ctx.GetSessionVars().PlanID = 0
-		ctx.GetSessionVars().PlanColumnID = 0
-	}
+	ctx.GetSessionVars().PlanID = 0
+	ctx.GetSessionVars().PlanColumnID = 0
 	switch x := node.(type) {
 	case *ast.SelectStmt:
 		defer func() {

planner/optimize.go

@@ -289,6 +289,25 @@ func Optimize(ctx context.Context, sctx sessionctx.Context, node ast.Node, is in
 	return bestPlan, names, nil
 }
 
+// OptimizeForForeignKeyCascade does optimization and creates a Plan for foreign key cascade.
+// The node must be prepared first.
+// Compare to Optimize, OptimizeForForeignKeyCascade only build plan by StmtNode,
+// doesn't consider plan cache and plan binding, also doesn't do privilege check.
+func OptimizeForForeignKeyCascade(ctx context.Context, sctx sessionctx.Context, node ast.StmtNode, is infoschema.InfoSchema) (core.Plan, error) {
+	builder := planBuilderPool.Get().(*core.PlanBuilder)
+	defer planBuilderPool.Put(builder.ResetForReuse())
+	hintProcessor := &hint.BlockHintProcessor{Ctx: sctx}
+	builder.Init(sctx, is, hintProcessor)
+	p, err := builder.Build(ctx, node)
+	if err != nil {
+		return nil, err
+	}
+	if err := core.CheckTableLock(sctx, is, builder.GetVisitInfo()); err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
 func allowInReadOnlyMode(sctx sessionctx.Context, node ast.Node) (bool, error) {
 	pm := privilege.GetPrivilegeManager(sctx)
 	if pm == nil {
@@ -428,11 +447,9 @@ func OptimizeExecStmt(ctx context.Context, sctx sessionctx.Context,
 }
 
 func buildLogicalPlan(ctx context.Context, sctx sessionctx.Context, node ast.Node, builder *core.PlanBuilder) (core.Plan, error) {
-	if !sctx.GetSessionVars().StmtCtx.InHandleForeignKeyTrigger {
-		sctx.GetSessionVars().PlanID = 0
-		sctx.GetSessionVars().PlanColumnID = 0
-		sctx.GetSessionVars().MapHashCode2UniqueID4ExtendedCol = nil
-	}
+	sctx.GetSessionVars().PlanID = 0
+	sctx.GetSessionVars().PlanColumnID = 0
+	sctx.GetSessionVars().MapHashCode2UniqueID4ExtendedCol = nil
 
 	failpoint.Inject("mockRandomPlanID", func() {
 		sctx.GetSessionVars().PlanID = rand.Intn(1000) // nolint:gosec