diff --git a/executor/grant_test.go b/executor/grant_test.go
index e16ec96c11..db198f94f4 100644
--- a/executor/grant_test.go
+++ b/executor/grant_test.go
@@ -183,19 +183,19 @@ func (s *testSuite) TestIssue2456(c *C) {
 
 func (s *testSuite) TestCreateUserWhenGrant(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
-	tk.MustExec("DROP USER IF EXISTS 'test'@'%'")
-	tk.MustExec("GRANT ALL PRIVILEGES ON *.* to 'test'@'%' IDENTIFIED BY 'xxx'")
+	tk.MustExec(`DROP USER IF EXISTS 'test'@'%'`)
+	tk.MustExec(`GRANT ALL PRIVILEGES ON *.* to 'test'@'%' IDENTIFIED BY 'xxx'`)
 	// Make sure user is created automatically when grant to a non-exists one.
-	tk.MustQuery("SELECT user FROM mysql.user WHERE user='test' and host='%'").Check(
+	tk.MustQuery(`SELECT user FROM mysql.user WHERE user='test' and host='%'`).Check(
 		testkit.Rows("test"),
 	)
 }
 
 func (s *testSuite) TestIssue2654(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
-	tk.MustExec("DROP USER IF EXISTS 'test'@'%'")
-	tk.MustExec("CREATE USER 'test'@'%' IDENTIFIED BY 'test'")
+	tk.MustExec(`DROP USER IF EXISTS 'test'@'%'`)
+	tk.MustExec(`CREATE USER 'test'@'%' IDENTIFIED BY 'test'`)
 	tk.MustExec("GRANT SELECT ON test.* to 'test'")
-	rows := tk.MustQuery("SELECT user,host FROM mysql.user WHERE user='test' and host='%'")
-	rows.Check(testkit.Rows("test %"))
+	rows := tk.MustQuery(`SELECT user,host FROM mysql.user WHERE user='test' and host='%'`)
+	rows.Check(testkit.Rows(`test %`))
 }
diff --git a/expression/evaluator_test.go b/expression/evaluator_test.go
index c19fde11fe..5bae92c1be 100644
--- a/expression/evaluator_test.go
+++ b/expression/evaluator_test.go
@@ -544,7 +544,7 @@ func (s *testEvaluatorSuite) TestLike(c *C) {
 		{"a", "a", 1},
 		{"a", "b", 0},
 		{"aA", "Aa", 0},
-		{"aAb", "Aa%", 0},
+		{"aAb", `Aa%`, 0},
 		{"aAb", "aA_", 1},
 	}
 	for _, tt := range tests {
diff --git a/expression/expr_to_pb_test.go b/expression/expr_to_pb_test.go
index f72b3964a3..ef52f28352 100644
--- a/expression/expr_to_pb_test.go
+++ b/expression/expr_to_pb_test.go
@@ -328,7 +328,7 @@ func (s *testEvaluatorSuite) TestLikeFunc2Pb(c *C) {
 	args := []Expression{
 		&Constant{RetType: retTp, Value: types.NewDatum("string")},
 		&Constant{RetType: retTp, Value: types.NewDatum("pattern")},
-		&Constant{RetType: retTp, Value: types.NewDatum("%abc%")},
+		&Constant{RetType: retTp, Value: types.NewDatum(`%abc%`)},
 		&Constant{RetType: retTp, Value: types.NewDatum("\\")},
 	}
 	ctx := mock.NewContext()
diff --git a/expression/integration_test.go b/expression/integration_test.go
index c41e449e19..de6a10d6b6 100644
--- a/expression/integration_test.go
+++ b/expression/integration_test.go
@@ -1378,11 +1378,11 @@ func (s *testIntegrationSuite) TestTimeBuiltin(c *C) {
 	result.Check(testkit.Rows("00:01:23 AM"))
 
 	// for date_format
-	result = tk.MustQuery("SELECT DATE_FORMAT('2017-06-15', '%W %M %e %Y %r %y');")
+	result = tk.MustQuery(`SELECT DATE_FORMAT('2017-06-15', '%W %M %e %Y %r %y');`)
 	result.Check(testkit.Rows("Thursday June 15 2017 12:00:00 AM 17"))
-	result = tk.MustQuery("SELECT DATE_FORMAT(151113102019.12, '%W %M %e %Y %r %y');")
+	result = tk.MustQuery(`SELECT DATE_FORMAT(151113102019.12, '%W %M %e %Y %r %y');`)
 	result.Check(testkit.Rows("Friday November 13 2015 10:20:19 AM 15"))
-	result = tk.MustQuery("SELECT DATE_FORMAT('0000-00-00', '%W %M %e %Y %r %y');")
+	result = tk.MustQuery(`SELECT DATE_FORMAT('0000-00-00', '%W %M %e %Y %r %y');`)
 	result.Check(testkit.Rows("<nil>"))
 
 	// for yearweek
@@ -2150,7 +2150,7 @@ func (s *testIntegrationSuite) TestBuiltin(c *C) {
 		{"a", "a", 1},
 		{"a", "b", 0},
 		{"aA", "Aa", 0},
-		{"aA%", "aAab", 1},
+		{`aA%`, "aAab", 1},
 		{"aA_", "Aaab", 0},
 		{"Aa_", "Aab", 1},
 		{"", "", 1},
diff --git a/expression/typeinfer_test.go b/expression/typeinfer_test.go
index 5ea9e68832..ac0b71e673 100644
--- a/expression/typeinfer_test.go
+++ b/expression/typeinfer_test.go
@@ -273,7 +273,7 @@ func (s *testInferTypeSuite) createTestCase4StrFuncs() []typeInferTestCase {
 		{"trim(c_binary)", mysql.TypeVarString, charset.CharsetBin, mysql.BinaryFlag, 20, types.UnspecifiedLength},
 		{"ascii(c_char)", mysql.TypeLonglong, charset.CharsetBin, mysql.BinaryFlag, 3, 0},
 		{"ord(c_char)", mysql.TypeLonglong, charset.CharsetBin, mysql.BinaryFlag, 10, 0},
-		{"c_int_d like 'abc%'", mysql.TypeLonglong, charset.CharsetBin, mysql.BinaryFlag, 1, 0},
+		{`c_int_d like 'abc%'`, mysql.TypeLonglong, charset.CharsetBin, mysql.BinaryFlag, 1, 0},
 		{"tidb_version()", mysql.TypeVarString, charset.CharsetUTF8, 0, len(printer.GetTiDBInfo()), types.UnspecifiedLength},
 		{"password(c_char)", mysql.TypeVarString, charset.CharsetUTF8, 0, mysql.PWDHashLen + 1, types.UnspecifiedLength},
 		{"elt(c_int_d, c_char, c_char, c_char)", mysql.TypeVarString, charset.CharsetUTF8, 0, 20, types.UnspecifiedLength},
@@ -1191,14 +1191,14 @@ func (s *testInferTypeSuite) createTestCase4OtherFuncs() []typeInferTestCase {
 
 func (s *testInferTypeSuite) createTestCase4TimeFuncs() []typeInferTestCase {
 	return []typeInferTestCase{
-		{"time_format('150:02:28', '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
-		{"time_format(123456, '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
-		{"time_format('bad string', '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
-		{"time_format(null, '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`time_format('150:02:28', '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`time_format(123456, '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`time_format('bad string', '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`time_format(null, '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
 
-		{"date_format(null, '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
-		{"date_format('2017-06-15', '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
-		{"date_format(151113102019.12, '%r%r%r%r')", mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`date_format(null, '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`date_format('2017-06-15', '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
+		{`date_format(151113102019.12, '%r%r%r%r')`, mysql.TypeVarString, charset.CharsetUTF8, 0, 44, types.UnspecifiedLength},
 
 		{"timestampadd(HOUR, c_int_d, c_timestamp_d)", mysql.TypeString, charset.CharsetUTF8, 0, 19, types.UnspecifiedLength},
 		{"timestampadd(minute, c_double_d, c_timestamp_d)", mysql.TypeString, charset.CharsetUTF8, 0, 19, types.UnspecifiedLength},
diff --git a/parser/parser_test.go b/parser/parser_test.go
index cd40e9b3ec..aea081687d 100644
--- a/parser/parser_test.go
+++ b/parser/parser_test.go
@@ -476,8 +476,8 @@ func (s *testParserSuite) TestDBAStmt(c *C) {
 		{"SHOW STATUS", true},
 		{"SHOW GLOBAL STATUS", true},
 		{"SHOW SESSION STATUS", true},
-		{"SHOW STATUS LIKE 'Up%'", true},
-		{"SHOW STATUS WHERE Variable_name LIKE 'Up%'", true},
+		{`SHOW STATUS LIKE 'Up%'`, true},
+		{`SHOW STATUS WHERE Variable_name LIKE 'Up%'`, true},
 		{`SHOW FULL TABLES FROM icar_qa LIKE play_evolutions`, true},
 		{`SHOW FULL TABLES WHERE Table_Type != 'VIEW'`, true},
 		{`SHOW GRANTS`, true},
@@ -505,7 +505,7 @@ func (s *testParserSuite) TestDBAStmt(c *C) {
 		{"show charset", true},
 		// for show collation
 		{"show collation", true},
-		{"show collation like 'utf8%'", true},
+		{`show collation like 'utf8%'`, true},
 		{"show collation where Charset = 'utf8' and Collation = 'utf8_bin'", true},
 		// for show full columns
 		{"show columns in t;", true},
@@ -868,7 +868,7 @@ func (s *testParserSuite) TestBuiltin(c *C) {
 		{"SELECT DATE('2003-12-31 01:02:03');", true},
 		{"SELECT DATE();", true},
 		{"SELECT DATE('2003-12-31 01:02:03', '');", true},
-		{"SELECT DATE_FORMAT('2003-12-31 01:02:03', '%W %M %Y');", true},
+		{`SELECT DATE_FORMAT('2003-12-31 01:02:03', '%W %M %Y');`, true},
 		{"SELECT DAY('2007-02-03');", true},
 		{"SELECT DAYOFMONTH('2007-02-03');", true},
 		{"SELECT DAYOFWEEK('2007-02-03');", true},
@@ -930,7 +930,7 @@ func (s *testParserSuite) TestBuiltin(c *C) {
 		{"SELECT SEC_TO_TIME(2378)", true},
 
 		// for TIME_FORMAT
-		{"SELECT TIME_FORMAT('100:00:00', '%H %k %h %I %l')", true},
+		{`SELECT TIME_FORMAT('100:00:00', '%H %k %h %I %l')`, true},
 
 		// for TIME_TO_SEC
 		{"SELECT TIME_TO_SEC('22:23:00')", true},
diff --git a/plan/physical_plan_test.go b/plan/physical_plan_test.go
index 91dc562c93..150d49a6ad 100644
--- a/plan/physical_plan_test.go
+++ b/plan/physical_plan_test.go
@@ -1015,7 +1015,7 @@ func (s *testPlanSuite) TestRefine(c *C) {
 			best: "TableReader(Table(t)->Sel([like(test.t.c_str, _abc, 92)]))->Projection",
 		},
 		{
-			sql:  "select a from t where c_str like 'abc%'",
+			sql:  `select a from t where c_str like 'abc%'`,
 			best: "IndexReader(Index(t.c_d_e_str)[[abc,abd)])->Projection",
 		},
 		{
diff --git a/session/bootstrap_test.go b/session/bootstrap_test.go
index b4d96a1301..66cb14bbad 100644
--- a/session/bootstrap_test.go
+++ b/session/bootstrap_test.go
@@ -55,7 +55,7 @@ func (s *testBootstrapSuite) TestBootstrap(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	datums := ast.RowToDatums(chk.GetRow(0), r.Fields())
-	match(c, datums, []byte("%"), []byte("root"), []byte(""), "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y")
+	match(c, datums, []byte(`%`), []byte("root"), []byte(""), "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y")
 
 	c.Assert(se.Auth(&auth.UserIdentity{Username: "root", Hostname: "anyhost"}, []byte(""), []byte("")), IsTrue)
 	mustExecSQL(c, se, "USE test;")
@@ -153,7 +153,7 @@ func (s *testBootstrapSuite) testBootstrapWithError(c *C) {
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	row := chk.GetRow(0)
 	datums := ast.RowToDatums(row, r.Fields())
-	match(c, datums, []byte("%"), []byte("root"), []byte(""), "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y")
+	match(c, datums, []byte(`%`), []byte("root"), []byte(""), "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y", "Y")
 	mustExecSQL(c, se, "USE test;")
 	// Check privilege tables.
 	mustExecSQL(c, se, "SELECT * from mysql.db;")
diff --git a/session/session_test.go b/session/session_test.go
index 63a8170a66..755bac23b7 100644
--- a/session/session_test.go
+++ b/session/session_test.go
@@ -564,8 +564,8 @@ func (s *testSessionSuite) TestSkipWithGrant(c *C) {
 	c.Assert(tk.Se.Auth(&auth.UserIdentity{Username: "user_not_exist"}, []byte("yyy"), []byte("zzz")), IsFalse)
 
 	privileges.SkipWithGrant = true
-	c.Assert(tk.Se.Auth(&auth.UserIdentity{Username: "xxx", Hostname: "%"}, []byte("yyy"), []byte("zzz")), IsTrue)
-	c.Assert(tk.Se.Auth(&auth.UserIdentity{Username: "root", Hostname: "%"}, []byte(""), []byte("")), IsTrue)
+	c.Assert(tk.Se.Auth(&auth.UserIdentity{Username: "xxx", Hostname: `%`}, []byte("yyy"), []byte("zzz")), IsTrue)
+	c.Assert(tk.Se.Auth(&auth.UserIdentity{Username: "root", Hostname: `%`}, []byte(""), []byte("")), IsTrue)
 	tk.MustExec("create table t (id int)")
 
 	privileges.Enable = save1
diff --git a/session/tidb_test.go b/session/tidb_test.go
index f5d2d344e9..0a41ff89e6 100644
--- a/session/tidb_test.go
+++ b/session/tidb_test.go
@@ -242,7 +242,7 @@ func newSession(c *C, store kv.Storage, dbName string) Session {
 	id := atomic.AddUint64(&testConnID, 1)
 	se.SetConnectionID(id)
 	c.Assert(err, IsNil)
-	se.Auth(&auth.UserIdentity{Username: "root", Hostname: "%"}, nil, []byte("012345678901234567890"))
+	se.Auth(&auth.UserIdentity{Username: "root", Hostname: `%`}, nil, []byte("012345678901234567890"))
 	mustExecSQL(c, se, "create database if not exists "+dbName)
 	mustExecSQL(c, se, "use "+dbName)
 	return se
diff --git a/util/prefix_helper_test.go b/util/prefix_helper_test.go
index 9e3e7c62c0..9edcef49a6 100644
--- a/util/prefix_helper_test.go
+++ b/util/prefix_helper_test.go
@@ -127,7 +127,7 @@ func (s *testPrefixSuite) TestPrefix(c *C) {
 	txn, err = s.s.Begin()
 	c.Assert(err, IsNil)
 	k := []byte("key100jfowi878230")
-	err = txn.Set(k, []byte("val32dfaskli384757^*&%^"))
+	err = txn.Set(k, []byte(`val32dfaskli384757^*&%^`))
 	c.Assert(err, IsNil)
 	err = util.ScanMetaWithPrefix(txn, k, func(kv.Key, []byte) bool {
 		return true
@@ -138,7 +138,7 @@ func (s *testPrefixSuite) TestPrefix(c *C) {
 }
 
 func (s *testPrefixSuite) TestPrefixFilter(c *C) {
-	rowKey := []byte("test@#$%l(le[0]..prefix) 2uio")
+	rowKey := []byte(`test@#$%l(le[0]..prefix) 2uio`)
 	rowKey[8] = 0x00
 	rowKey[9] = 0x00
 	f := util.RowKeyPrefixFilter(rowKey)