diff --git a/main.go b/main.go
index de6ce428..993e19b1 100644
--- a/main.go
+++ b/main.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"reflect"
 	"strings"
+	"sync"
 	"time"
 )
 
@@ -162,7 +163,7 @@ func (s *DB) HasBlockGlobalUpdate() bool {
 
 // SingularTable use singular table by default
 func (s *DB) SingularTable(enable bool) {
-	modelStructsMap = newModelStructsMap()
+	modelStructsMap = sync.Map{}
 	s.parent.singularTable = enable
 }
 
diff --git a/model_struct.go b/model_struct.go
index 79df79f7..0ef534a5 100644
--- a/model_struct.go
+++ b/model_struct.go
@@ -17,9 +17,7 @@ var DefaultTableNameHandler = func(db *DB, defaultTableName string) string {
 	return defaultTableName
 }
 
-func newModelStructsMap() sync.Map { return sync.Map{} }
-
-var modelStructsMap = newModelStructsMap()
+var modelStructsMap sync.Map
 
 // ModelStruct model definition
 type ModelStruct struct {