diff --git a/advisor/heuristic.go b/advisor/heuristic.go
index 780e38ee03826649b4d59aea3916b4f31f33fa26..a7c2e7e72982a1600a1be3e00f5e2806f60c4276 100644
--- a/advisor/heuristic.go
+++ b/advisor/heuristic.go
@@ -107,7 +107,7 @@ func (q *Query4Audit) RulePrefixLike() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch expr := node.(type) {
 		case *sqlparser.ComparisonExpr:
-			if expr.Operator == "like" {
+			if strings.ToLower(expr.Operator) == "like" {
 				switch sqlval := expr.Right.(type) {
 				case *sqlparser.SQLVal:
 					// prefix like with '%', '_'
@@ -130,7 +130,7 @@ func (q *Query4Audit) RuleEqualLike() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch expr := node.(type) {
 		case *sqlparser.ComparisonExpr:
-			if expr.Operator == "like" {
+			if strings.ToLower(expr.Operator) == "like" {
 				switch sqlval := expr.Right.(type) {
 				case *sqlparser.SQLVal:
 					// not start with '%', '_' && not end with '%', '_'
@@ -397,7 +397,7 @@ func (q *Query4Audit) RuleOrderByRand() Rule {
 			for _, order := range n {
 				switch expr := order.Expr.(type) {
 				case *sqlparser.FuncExpr:
-					if expr.Name.String() == "rand" {
+					if strings.ToLower(expr.Name.String()) == "rand" {
 						rule = HeuristicRules["CLA.002"]
 						return false, nil
 					}
@@ -761,7 +761,7 @@ func (q *Query4Audit) RuleTblCommentCheck() Rule {
 	var rule = q.RuleOK()
 	switch node := q.Stmt.(type) {
 	case *sqlparser.DDL:
-		if node.Action != "create" {
+		if strings.ToLower(node.Action) != "create" {
 			return rule
 		}
 		if node.TableSpec == nil {
@@ -968,7 +968,7 @@ func (q *Query4Audit) RuleSQLCalcFoundRows() Rule {
 	var rule = q.RuleOK()
 	tkns := ast.Tokenizer(q.Query)
 	for _, tkn := range tkns {
-		if tkn.Val == "sql_calc_found_rows" {
+		if strings.ToLower(tkn.Val) == "sql_calc_found_rows" {
 			rule = HeuristicRules["KWR.001"]
 			break
 		}
@@ -1049,7 +1049,7 @@ func (idxAdv *IndexAdvisor) RuleImpossibleOuterJoin() Rule {
 
 	for _, l1 := range idxAdv.joinCond {
 		for _, l2 := range l1 {
-			if l2.Table != "" && l2.Table != "dual" {
+			if l2.Table != "" && strings.ToLower(l2.Table) != "dual" {
 				joinTables = append(joinTables, l2.Table)
 			}
 		}
@@ -1192,7 +1192,7 @@ func (q *Query4Audit) RuleImpossibleWhere() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch n := node.(type) {
 		case *sqlparser.RangeCond:
-			if n.Operator == "between" {
+			if strings.ToLower(n.Operator) == "between" {
 				from := 0
 				to := 0
 				switch s := n.From.(type) {
@@ -1893,7 +1893,7 @@ func (q *Query4Audit) RuleSysdate() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch n := node.(type) {
 		case *sqlparser.FuncExpr:
-			if n.Name.String() == "sysdate" {
+			if strings.ToLower(n.Name.String()) == "sysdate" {
 				rule = HeuristicRules["FUN.004"]
 				return false, nil
 			}
@@ -2161,7 +2161,7 @@ func (idxAdv *IndexAdvisor) RuleUpdatePrimaryKey() Rule {
 				return rule
 			}
 			for _, idx := range idxMeta.Rows {
-				if idx.KeyName == "PRIMARY" {
+				if strings.ToLower(idx.KeyName) == "primary" {
 					if col.Name == idx.ColumnName {
 						rule = HeuristicRules["CLA.016"]
 						return rule
@@ -2310,7 +2310,7 @@ func (q *Query4Audit) RuleNot() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch n := node.(type) {
 		case *sqlparser.ComparisonExpr:
-			if strings.HasPrefix(n.Operator, "not") {
+			if strings.HasPrefix(strings.ToLower(n.Operator), "not") {
 				rule = HeuristicRules["ARG.011"]
 				return false, nil
 			}
@@ -2359,7 +2359,7 @@ func (q *Query4Audit) RuleUNIONUsage() Rule {
 	var rule = q.RuleOK()
 	switch s := q.Stmt.(type) {
 	case *sqlparser.Union:
-		if s.Type == "union" {
+		if strings.ToLower(s.Type) == "union" {
 			rule = HeuristicRules["SUB.002"]
 		}
 	}
@@ -2435,11 +2435,11 @@ func (q *Query4Audit) RuleDataDrop() Rule {
 	var rule = q.RuleOK()
 	switch s := q.Stmt.(type) {
 	case *sqlparser.DBDDL:
-		if s.Action == "drop" {
+		if strings.ToLower(s.Action) == "drop" {
 			rule = HeuristicRules["SEC.003"]
 		}
 	case *sqlparser.DDL:
-		if s.Action == "drop" || s.Action == "truncate" {
+		if strings.ToLower(s.Action) == "drop" || strings.ToLower(s.Action) == "truncate" {
 			rule = HeuristicRules["SEC.003"]
 		}
 	case *sqlparser.Delete:
@@ -2523,7 +2523,7 @@ func (q *Query4Audit) RuleTruncateTable() Rule {
 	var rule = q.RuleOK()
 	switch s := q.Stmt.(type) {
 	case *sqlparser.DDL:
-		if s.Action == "truncate" {
+		if strings.ToLower(s.Action) == "truncate" {
 			rule = HeuristicRules["SEC.001"]
 		}
 	}
@@ -2536,7 +2536,7 @@ func (q *Query4Audit) RuleIn() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch n := node.(type) {
 		case *sqlparser.ComparisonExpr:
-			switch n.Operator {
+			switch strings.ToLower(n.Operator) {
 			case "in":
 				switch r := n.Right.(type) {
 				case sqlparser.ValTuple:
@@ -2842,12 +2842,12 @@ func (q *Query4Audit) RulePKNotInt() Rule {
 	var pk sqlparser.ColIdent
 	switch s := q.Stmt.(type) {
 	case *sqlparser.DDL:
-		if s.Action == "create" {
+		if strings.ToLower(s.Action) == "create" {
 			if s.TableSpec == nil {
 				return rule
 			}
 			for _, idx := range s.TableSpec.Indexes {
-				if idx.Info.Type == "primary key" {
+				if strings.ToLower(idx.Info.Type) == "primary key" {
 					if len(idx.Columns) == 1 {
 						pk = idx.Columns[0].Column
 						break
@@ -2864,7 +2864,7 @@ func (q *Query4Audit) RulePKNotInt() Rule {
 			// 主键非int, bigint类型
 			for _, col := range s.TableSpec.Columns {
 				if pk.String() == col.Name.String() {
-					switch col.Type.Type {
+					switch strings.ToLower(col.Type.Type) {
 					case "int", "bigint", "integer":
 						if !col.Type.Unsigned {
 							rule = HeuristicRules["KEY.007"]
@@ -2971,7 +2971,7 @@ func (q *Query4Audit) RuleFulltextIndex() Rule {
 	for _, tk := range tks {
 		switch tk.Type {
 		case ast.TokenTypeWord:
-			if strings.TrimSpace(strings.ToUpper(tk.Val)) == "FULLTEXT" {
+			if strings.TrimSpace(strings.ToLower(tk.Val)) == "fulltext" {
 				rule = HeuristicRules["KEY.010"]
 			}
 		default:
@@ -3001,8 +3001,8 @@ func (q *Query4Audit) RuleTimestampDefault() Rule {
 							if option.Tp == tidb.ColumnOptionDefaultValue {
 								hasDefault = true
 								if err := option.Restore(ctx); err == nil {
-									if strings.HasPrefix(sb.String(), `DEFAULT '0`) ||
-										strings.HasPrefix(sb.String(), `DEFAULT 0`) {
+									if strings.HasPrefix(strings.ToLower(sb.String()), `default '0`) ||
+										strings.HasPrefix(strings.ToLower(sb.String()), `default 0`) {
 										hasDefault = false
 									}
 								}
@@ -3034,8 +3034,8 @@ func (q *Query4Audit) RuleTimestampDefault() Rule {
 									if option.Tp == tidb.ColumnOptionDefaultValue {
 										hasDefault = true
 										if err := option.Restore(ctx); err == nil {
-											if strings.HasPrefix(sb.String(), `DEFAULT '0`) ||
-												strings.HasPrefix(sb.String(), `DEFAULT 0`) {
+											if strings.HasPrefix(strings.ToLower(sb.String()), `default '0`) ||
+												strings.HasPrefix(strings.ToLower(sb.String()), `default 0`) {
 												hasDefault = false
 											}
 										}
@@ -3464,7 +3464,7 @@ func (q *Query4Audit) RuleColumnNotAllowType() Rule {
 
 	switch s := q.Stmt.(type) {
 	case *sqlparser.DDL:
-		switch s.Action {
+		switch strings.ToLower(s.Action) {
 		case "create", "alter":
 			tks := ast.Tokenize(q.Query)
 			for _, tk := range tks {
@@ -3536,7 +3536,7 @@ func (q *Query4Audit) RuleNoOSCKey() Rule {
 	var rule = q.RuleOK()
 	switch s := q.Stmt.(type) {
 	case *sqlparser.DDL:
-		if s.Action == "create" {
+		if strings.ToLower(s.Action) == "create" {
 			pkReg := regexp.MustCompile(`(?i)(primary\s+key)`)
 			if !pkReg.MatchString(q.Query) {
 				ukReg := regexp.MustCompile(`(?i)(unique\s+((key)|(index)))`)
@@ -3605,7 +3605,7 @@ func (idxAdv *IndexAdvisor) RuleMaxTextColsCount() Rule {
 	err := sqlparser.Walk(func(node sqlparser.SQLNode) (kontinue bool, err error) {
 		switch stmt := node.(type) {
 		case *sqlparser.DDL:
-			if stmt.Action != "alter" {
+			if strings.ToLower(stmt.Action) != "alter" {
 				return true, nil
 			}
 
diff --git a/advisor/heuristic_test.go b/advisor/heuristic_test.go
index 8b2d63bdbb87a83d5f35006060d3167cdb662512..8fb25842523165f3e7885b26f0e9a98a97eeb0fe 100644
--- a/advisor/heuristic_test.go
+++ b/advisor/heuristic_test.go
@@ -1575,6 +1575,7 @@ func TestRuleSysdate(t *testing.T) {
 	common.Log.Debug("Entering function: %s", common.GetFunctionName())
 	sqls := []string{
 		`select sysdate();`,
+		`select Sysdate();`,
 	}
 	for _, sql := range sqls {
 		q, err := NewQuery4Audit(sql)
@@ -2435,6 +2436,7 @@ func TestRuleInjection(t *testing.T) {
 		{
 			`select benchmark(10, rand())`,
 			`select sleep(1)`,
+			`select Sleep(1)`,
 			`select get_lock('lock_name', 1)`,
 			`select release_lock('lock_name')`,
 		},
@@ -2542,6 +2544,7 @@ func TestRuleTruncateTable(t *testing.T) {
 	common.Log.Debug("Entering function: %s", common.GetFunctionName())
 	sqls := []string{
 		`TRUNCATE TABLE tbl_name;`,
+		`truncate TABLE tbl_name;`,
 	}
 	for _, sql := range sqls {
 		q, err := NewQuery4Audit(sql)
@@ -2861,6 +2864,7 @@ func TestRulePKNotInt(t *testing.T) {
 		},
 		{
 			"CREATE TABLE tbl (a int unsigned auto_increment, b int, primary key(`a`)) engine=InnoDB;",
+			"CREATE TABLE `tb` ( `id` Bigint unsigned NOT NULL AUTO_INCREMENT COMMENT 'auto id', Primary  key (`id`) ) ENGINE = InnoDB COMMENT 'comment'",
 		},
 	}
 	for _, sql := range sqls[0] {