diff --git a/executor/issuetest/executor_issue_test.go b/executor/issuetest/executor_issue_test.go
index 6c132ef088f87..b025bf1116710 100644
--- a/executor/issuetest/executor_issue_test.go
+++ b/executor/issuetest/executor_issue_test.go
@@ -682,7 +682,7 @@ func TestIssue22231(t *testing.T) {
 	tk.MustExec("create table t_issue_22231(a datetime)")
 	tk.MustExec("insert into t_issue_22231 values('2020--05-20 01:22:12')")
 	tk.MustQuery("select * from t_issue_22231 where a >= '2020-05-13 00:00:00 00:00:00' and a <= '2020-05-28 23:59:59 00:00:00'").Check(testkit.Rows("2020-05-20 01:22:12"))
-	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1292 Truncated incorrect datetime value: '2020-05-13 00:00:00 00:00:00'", "Warning 1292 Truncated incorrect datetime value: '2020-05-28 23:59:59 00:00:00'"))
+	tk.MustQuery("show warnings").MultiCheckContain([]string{"Truncated incorrect datetime value: '2020-05-13 00:00:00 00:00:00'", "Truncated incorrect datetime value: '2020-05-28 23:59:59 00:00:00'"})
 
 	tk.MustQuery("select cast('2020-10-22 10:31-10:12' as datetime)").Check(testkit.Rows("2020-10-22 10:31:10"))
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1292 Truncated incorrect datetime value: '2020-10-22 10:31-10:12'"))
diff --git a/expression/integration_serial_test/integration_serial_test.go b/expression/integration_serial_test/integration_serial_test.go
index 6aeb23c64f919..64510e7742ee9 100644
--- a/expression/integration_serial_test/integration_serial_test.go
+++ b/expression/integration_serial_test/integration_serial_test.go
@@ -2300,7 +2300,7 @@ func TestTimeBuiltin(t *testing.T) {
 	tk.MustExec(`update t set a = dayOfMonth("0000-00-00")`)
 	tk.MustExec("set sql_mode = 'NO_ZERO_DATE';")
 	tk.MustExec("insert into t value(dayOfMonth('0000-00-00'))")
-	tk.MustQuery("show warnings").Check(testkit.RowsWithSep("|", "Warning|1292|Incorrect datetime value: '0000-00-00 00:00:00.000000'"))
+	tk.MustQuery("show warnings").CheckContain("Incorrect datetime value: '0000-00-00 00:00:00.000000'")
 	tk.MustExec(`update t set a = dayOfMonth("0000-00-00")`)
 	tk.MustExec("set sql_mode = 'NO_ZERO_DATE,STRICT_TRANS_TABLES';")
 	_, err = tk.Exec("insert into t value(dayOfMonth('0000-00-00'))")
@@ -2395,7 +2395,7 @@ func TestTimeBuiltin(t *testing.T) {
 	tk.MustExec(`update t set a = monthname("0000-00-00")`)
 	tk.MustExec("set sql_mode = 'NO_ZERO_DATE'")
 	tk.MustExec("insert into t value(monthname('0000-00-00'))")
-	tk.MustQuery("show warnings").Check(testkit.RowsWithSep("|", "Warning|1292|Incorrect datetime value: '0000-00-00 00:00:00.000000'"))
+	tk.MustQuery("show warnings").CheckContain("Incorrect datetime value: '0000-00-00 00:00:00.000000'")
 	tk.MustExec(`update t set a = monthname("0000-00-00")`)
 	tk.MustExec("set sql_mode = ''")
 	tk.MustExec("insert into t value(monthname('0000-00-00'))")
@@ -2406,7 +2406,7 @@ func TestTimeBuiltin(t *testing.T) {
 	require.NoError(t, err)
 	result = tk.MustQuery(`select monthname("2017-12-01"), monthname("0000-00-00"), monthname("0000-01-00"), monthname("0000-01-00 00:00:00")`)
 	result.Check(testkit.Rows("December <nil> January January"))
-	tk.MustQuery("show warnings").Check(testkit.RowsWithSep("|", "Warning|1292|Incorrect datetime value: '0000-00-00 00:00:00.000000'"))
+	tk.MustQuery("show warnings").CheckContain("Incorrect datetime value: '0000-00-00 00:00:00.000000'")
 
 	// for dayname
 	tk.MustExec(`drop table if exists t`)
diff --git a/expression/integration_test/integration_test.go b/expression/integration_test/integration_test.go
index e59e03af081dc..f20f33097a494 100644
--- a/expression/integration_test/integration_test.go
+++ b/expression/integration_test/integration_test.go
@@ -1711,7 +1711,7 @@ func TestArithmeticBuiltin(t *testing.T) {
 	tk.MustExec("drop table if exists t;")
 	tk.MustExec("CREATE TABLE t (v int);")
 	tk.MustExec("INSERT IGNORE INTO t VALUE(12 MOD 0);")
-	tk.MustQuery("show warnings;").Check(testkit.Rows("Warning 1365 Division by 0"))
+	tk.MustQuery("show warnings;").CheckContain("Division by 0")
 	tk.MustQuery("select v from t;").Check(testkit.Rows("<nil>"))
 	tk.MustQuery("select 0.000 % 0.11234500000000000000;").Check(testkit.Rows("0.00000000000000000000"))
 
@@ -7172,7 +7172,7 @@ func TestIssue29708(t *testing.T) {
 	})
 
 	tk.MustExec("INSERT IGNORE INTO t1 VALUES (REPEAT(0125,200000000));")
-	tk.MustQuery("show warnings;").Check(testkit.Rows("Warning 1301 Result of repeat() was larger than max_allowed_packet (67108864) - truncated"))
+	tk.MustQuery("show warnings;").CheckContain("Result of repeat() was larger than max_allowed_packet (67108864) - truncated")
 	tk.MustQuery("select a from t1 order by a;").Check([][]interface{}{
 		{nil},
 		{"a"},
diff --git a/parser/format/format.go b/parser/format/format.go
index a4ac72532519d..31d760d98b70f 100644
--- a/parser/format/format.go
+++ b/parser/format/format.go
@@ -377,7 +377,7 @@ func (ctx *RestoreCtx) WriteKeyWord(keyWord string) {
 	case ctx.Flags.HasKeyWordLowercaseFlag():
 		keyWord = strings.ToLower(keyWord)
 	}
-	fmt.Fprint(ctx.In, keyWord)
+	ctx.In.WriteString(keyWord)
 }
 
 // WriteWithSpecialComments writes a string with a special comment wrapped.
@@ -412,7 +412,9 @@ func (ctx *RestoreCtx) WriteString(str string) {
 		str = strings.Replace(str, `"`, `""`, -1)
 		quotes = `"`
 	}
-	fmt.Fprint(ctx.In, quotes, str, quotes)
+	ctx.In.WriteString(quotes)
+	ctx.In.WriteString(str)
+	ctx.In.WriteString(quotes)
 }
 
 // WriteName writes the name into writer
diff --git a/planner/core/integration_test.go b/planner/core/integration_test.go
index 77bd80146a044..db94217d8e110 100644
--- a/planner/core/integration_test.go
+++ b/planner/core/integration_test.go
@@ -4940,7 +4940,7 @@ func TestIssue37760(t *testing.T) {
 	tk.MustExec("insert into t values (2), (4), (6)")
 	tk.MustExec("set @@tidb_opt_range_max_size=1")
 	tk.MustQuery("select * from t where a").Check(testkit.Rows("2", "4", "6"))
-	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1105 Memory capacity of 1 bytes for 'tidb_opt_range_max_size' exceeded when building ranges. Less accurate ranges such as full range are chosen"))
+	tk.MustQuery("show warnings").CheckContain("Memory capacity of 1 bytes for 'tidb_opt_range_max_size' exceeded when building ranges. Less accurate ranges such as full range are chosen")
 }
 
 // TestExplainAnalyzeDMLCommit covers the issue #37373.
diff --git a/planner/core/plan_cache_param.go b/planner/core/plan_cache_param.go
index 1e2d808bcf231..abd8ce679f9c6 100644
--- a/planner/core/plan_cache_param.go
+++ b/planner/core/plan_cache_param.go
@@ -72,8 +72,8 @@ func (pr *paramReplacer) Enter(in ast.Node) (out ast.Node, skipChildren bool) {
 		}
 	case *driver.ValueExpr:
 		pr.params = append(pr.params, n)
-		param := ast.NewParamMarkerExpr(len(pr.params) - 1)      // offset is used as order in non-prepared plan cache.
-		param.(*driver.ParamMarkerExpr).Datum = *n.Datum.Clone() // init the ParamMakerExpr's Datum
+		param := ast.NewParamMarkerExpr(len(pr.params) - 1)  // offset is used as order in non-prepared plan cache.
+		n.Datum.Copy(&param.(*driver.ParamMarkerExpr).Datum) // init the ParamMakerExpr's Datum
 		return param, true
 	}
 	return in, false
diff --git a/planner/core/plan_cache_test.go b/planner/core/plan_cache_test.go
index 3af6cb3c1b8b5..bc75ffd1d0e3d 100644
--- a/planner/core/plan_cache_test.go
+++ b/planner/core/plan_cache_test.go
@@ -103,6 +103,41 @@ func TestIssue40296(t *testing.T) {
 	tk.MustQuery("select @@last_plan_from_cache").Check(testkit.Rows("0")) // unary operator '-' is not supported now.
 }
 
+func TestNonPreparedPlanCacheDMLHints(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec(`use test`)
+	tk.MustExec(`create table t (a int)`)
+	tk.MustExec(`set @@tidb_enable_non_prepared_plan_cache=1`)
+
+	tk.MustExec(`insert into t values (1)`)
+	tk.MustExec(`insert into t values (1)`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+	tk.MustExec(`update t set a=1`)
+	tk.MustExec(`update t set a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+	tk.MustExec(`delete from t where a=1`)
+	tk.MustExec(`delete from t where a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+
+	tk.MustExec(`insert /*+ ignore_plan_cache() */ into t values (1)`)
+	tk.MustExec(`insert /*+ ignore_plan_cache() */ into t values (1)`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("0"))
+	tk.MustExec(`update /*+ ignore_plan_cache() */ t set a=1`)
+	tk.MustExec(`update /*+ ignore_plan_cache() */ t set a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("0"))
+	tk.MustExec(`delete /*+ ignore_plan_cache() */ from t where a=1`)
+	tk.MustExec(`delete /*+ ignore_plan_cache() */ from t where a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("0"))
+
+	tk.MustExec(`insert into t values (1)`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+	tk.MustExec(`update t set a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+	tk.MustExec(`delete from t where a=1`)
+	tk.MustQuery(`select @@last_plan_from_cache`).Check(testkit.Rows("1"))
+}
+
 func TestNonPreparedPlanCachePlanString(t *testing.T) {
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)
diff --git a/planner/core/plan_cache_utils.go b/planner/core/plan_cache_utils.go
index 31d2a3fd7191b..ea5d816664370 100644
--- a/planner/core/plan_cache_utils.go
+++ b/planner/core/plan_cache_utils.go
@@ -186,6 +186,7 @@ func GeneratePlanCacheStmtWithAST(ctx context.Context, sctx sessionctx.Context,
 // Put the parameters that may affect the plan in planCacheValue.
 // However, due to some compatibility reasons, we will temporarily keep some system variable-related values in planCacheKey.
 // At the same time, because these variables have a small impact on plan, we will move them to PlanCacheValue later if necessary.
+// TODO: maintain a sync.pool for this structure.
 type planCacheKey struct {
 	database      string
 	connID        uint64
@@ -214,14 +215,10 @@ type planCacheKey struct {
 // Hash implements Key interface.
 func (key *planCacheKey) Hash() []byte {
 	if len(key.hash) == 0 {
-		var (
-			dbBytes    = hack.Slice(key.database)
-			bufferSize = len(dbBytes) + 8*6 + 3*8
-		)
 		if key.hash == nil {
-			key.hash = make([]byte, 0, bufferSize)
+			key.hash = make([]byte, 0, len(key.stmtText)*2)
 		}
-		key.hash = append(key.hash, dbBytes...)
+		key.hash = append(key.hash, hack.Slice(key.database)...)
 		key.hash = codec.EncodeInt(key.hash, int64(key.connID))
 		key.hash = append(key.hash, hack.Slice(key.stmtText)...)
 		key.hash = codec.EncodeInt(key.hash, key.schemaVersion)
@@ -496,6 +493,12 @@ func (checker *matchOptsExtractor) Enter(in ast.Node) (out ast.Node, skipChildre
 		}
 		tStats := getStatsTable(checker.sctx, t.Meta(), t.Meta().ID)
 		checker.statsVersionHash += tableStatsVersionForPlanCache(tStats) // use '+' as the hash function for simplicity
+	case *ast.InsertStmt:
+		if node.Select != nil {
+			node.Select.Accept(checker)
+		}
+		// skip node.Table for performance.
+		return in, true
 	}
 	return in, false
 }
diff --git a/planner/core/plan_cacheable_checker.go b/planner/core/plan_cacheable_checker.go
index 61bd1d884b7ac..228d0678a11a7 100644
--- a/planner/core/plan_cacheable_checker.go
+++ b/planner/core/plan_cacheable_checker.go
@@ -225,6 +225,9 @@ func NonPreparedPlanCacheableWithCtx(sctx sessionctx.Context, node ast.Node, is
 			return ok, reason
 		}
 	case *ast.UpdateStmt:
+		if len(x.TableHints) > 0 {
+			return false, "not support update statement with table hints"
+		}
 		if x.MultipleTable {
 			return false, "not support multiple tables update statements"
 		}
@@ -233,6 +236,9 @@ func NonPreparedPlanCacheableWithCtx(sctx sessionctx.Context, node ast.Node, is
 			return ok, reason
 		}
 	case *ast.InsertStmt:
+		if len(x.TableHints) > 0 {
+			return false, "not support insert statement with table hints"
+		}
 		if x.Select == nil { // `insert into t values (...)`
 			nRows := len(x.Lists)
 			nCols := 0
@@ -261,6 +267,9 @@ func NonPreparedPlanCacheableWithCtx(sctx sessionctx.Context, node ast.Node, is
 			}
 		}
 	case *ast.DeleteStmt:
+		if len(x.TableHints) > 0 {
+			return false, "not support insert statement with table hints"
+		}
 		if x.IsMultiTable {
 			return false, "not support multiple tables delete statements"
 		}