Data Access has been discontinued. Please refer to this page for more information.

The Type For Member Of The Persistent Class Is Not a Valid Mapping For Its Column

This article is relevant to entity models that utilize the deprecated Visual Studio integration of Telerik Data Access. The current documentation of the Data Access framework is available here.

This error occurs when a property in the Visual Designer is of CLR type that cannot be mapped to the SQL type of the corresponding database column. For example, the Address property of the Customer entity is of type 'string'. However, the corresponding database column is of type 'int'.


To resolve this error, synchronize the primitive member's CLR type with the column's SQL type. If you want to modify the SQL type of the column, you should use the Table Editor:

  1. Right-click the entity in Visual Designer and select Edit Table... from the context menu.
  2. In the Table Editor find the corresponding column and change the *SQL type *setting.

If you want to change the CLR type of the property, you should use the Properties pane:

  1. In the Visual Designer, select the property.
  2. Press F4 to open the Properties pane.
  3. Change the Type property.