diff --git a/gorm.go b/gorm.go
index 7f7bad26..71cd01e8 100644
--- a/gorm.go
+++ b/gorm.go
@@ -387,44 +387,46 @@ func (db *DB) SetupJoinTable(model interface{}, field string, joinTable interfac
 		modelSchema, joinSchema *schema.Schema
 	)
 
-	if err := stmt.Parse(model); err == nil {
-		modelSchema = stmt.Schema
-	} else {
+	err := stmt.Parse(model)
+	if err != nil {
 		return err
 	}
+	modelSchema = stmt.Schema
 
-	if err := stmt.Parse(joinTable); err == nil {
-		joinSchema = stmt.Schema
-	} else {
+	err = stmt.Parse(joinTable)
+	if err != nil {
 		return err
 	}
+	joinSchema = stmt.Schema
 
-	if relation, ok := modelSchema.Relationships.Relations[field]; ok && relation.JoinTable != nil {
-		for _, ref := range relation.References {
-			if f := joinSchema.LookUpField(ref.ForeignKey.DBName); f != nil {
-				f.DataType = ref.ForeignKey.DataType
-				f.GORMDataType = ref.ForeignKey.GORMDataType
-				if f.Size == 0 {
-					f.Size = ref.ForeignKey.Size
-				}
-				ref.ForeignKey = f
-			} else {
-				return fmt.Errorf("missing field %s for join table", ref.ForeignKey.DBName)
-			}
-		}
-
-		for name, rel := range relation.JoinTable.Relationships.Relations {
-			if _, ok := joinSchema.Relationships.Relations[name]; !ok {
-				rel.Schema = joinSchema
-				joinSchema.Relationships.Relations[name] = rel
-			}
-		}
-
-		relation.JoinTable = joinSchema
-	} else {
+	relation, ok := modelSchema.Relationships.Relations[field]
+	isRelation := ok && relation.JoinTable != nil
+	if !isRelation {
 		return fmt.Errorf("failed to found relation: %s", field)
 	}
 
+	for _, ref := range relation.References {
+		f := joinSchema.LookUpField(ref.ForeignKey.DBName)
+		if f == nil {
+			return fmt.Errorf("missing field %s for join table", ref.ForeignKey.DBName)
+		}
+
+		f.DataType = ref.ForeignKey.DataType
+		f.GORMDataType = ref.ForeignKey.GORMDataType
+		if f.Size == 0 {
+			f.Size = ref.ForeignKey.Size
+		}
+		ref.ForeignKey = f
+	}
+
+	for name, rel := range relation.JoinTable.Relationships.Relations {
+		if _, ok := joinSchema.Relationships.Relations[name]; !ok {
+			rel.Schema = joinSchema
+			joinSchema.Relationships.Relations[name] = rel
+		}
+	}
+	relation.JoinTable = joinSchema
+
 	return nil
 }