if field == nil {
			continue
		}

		if len(joinFields) == 0 || len(joinFields[idx]) == 0 {
			db.AddError(field.Set(db.Statement.Context, reflectValue, values[idx]))
		} else { // joinFields count is larger than 2 when using join
			var isNilPtrValue bool
			var relValue reflect.Value
			// does not contain raw dbname
			nestedJoinSchemas := joinFields[idx][:len(joinFields[idx])-1]
			// current reflect value