报如下错误是怎么回事!!!!急
Cannot include Memo, OLE, or Hyperlink Object when you select unique values (Composition).
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.OleDb.OleDbException: Cannot include Memo, OLE, or Hyperlink Object when you select unique values (Composition).
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[OleDbException (0x80040e21): Cannot include Memo, OLE, or Hyperlink Object when you select unique values (Composition).]
System.Data.OleDb.OleDbCommand.ExecuteCommandTextErrorHandling(Int32 hr) +41
System.Data.OleDb.OleDbCommand.ExecuteCommandTextForSingleResult(tagDBPARAMS dbParams, Object& executeResult) +174
System.Data.OleDb.OleDbCommand.ExecuteCommandText(Object& executeResult) +92
System.Data.OleDb.OleDbCommand.ExecuteCommand(CommandBehavior behavior, Object& executeResult) +65
System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior, String method) +112
System.Data.OleDb.OleDbCommand.ExecuteReader(CommandBehavior behavior) +69
BWJCare2.DAL.Mims.SelectOne(String guid) +161
BWJCare2.BIZ.BMims.SelectOne(String guid) +34
BWJCare2.WEB.Medication_Detail.ShowInfo(String str) +44
BWJCare2.WEB.Medication_Detail.druglist_SelectedIndexChanged(Object sender, EventArgs e) +189
System.Web.UI.WebControls.ListControl.OnSelectedIndexChanged(EventArgs e) +108
System.Web.UI.WebControls.DropDownList.System.Web.UI.IPostBackDataHandler.RaisePostDataChangedEvent() +26
System.Web.UI.Page.RaiseChangedEvents() +115
System.Web.UI.Page.ProcessRequestMain() +1081