Concurrency Troubles using Access as Database '?' Appear in SQL

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From: Daren Hawes (Newsgroups_at_webdesignmagic.com.au)
Date: 12/06/04 

Date: Tue, 7 Dec 2004 09:09:52 +1000

Hi,
 
I am using access as the main DB for an application.
 
Whenever I try to update the DB by my Dataset I get Exception below.
 
--------------
An unhandled exception of type 'System.Data.DBConcurrencyException'
occurred in system.data.dll
 
Additional information: Concurrency violation: the DeleteCommand
affected 0 records.
--------------
 
What worries me is the "?" in the SQL below of the Update Command? Is
this normal?
I just cannot get my head around the "?"
 
All the code below was generated by Visual Studio.
 
Do I have to modify this or am I doing something Wrong?
 
Thanks in Advance.
 
 
'OleDbUpdateCommand1

'

Me.OleDbUpdateCommand1.CommandText = "UPDATE Reminders SET ReminderDate
= ?, ReminderTime = ?, Route = ? WHERE (EventID" & _

" = ?) AND (ReminderDate = ? OR ? IS NULL AND ReminderDate IS NULL) AND
(Reminder" & _

"Time = ? OR ? IS NULL AND ReminderTime IS NULL) AND (Route = ? OR ? IS
NULL AND " & _

"Route IS NULL)"

Me.OleDbUpdateCommand1.Connection = Me.OleDbConnection

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("ReminderDate",
System.Data.OleDb.OleDbType.DBDate, 0, "ReminderDate"))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("ReminderTime",
System.Data.OleDb.OleDbType.DBDate, 0, "ReminderTime"))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Route",
System.Data.OleDb.OleDbType.VarWChar, 50, "Route"))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_EventID",
System.Data.OleDb.OleDbType.Integer, 0,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "EventID", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_ReminderDate",
System.Data.OleDb.OleDbType.DBDate, 0,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "ReminderDate", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_ReminderDate1",
System.Data.OleDb.OleDbType.DBDate, 0,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "ReminderDate", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_ReminderTime",
System.Data.OleDb.OleDbType.DBDate, 0,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "ReminderTime", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_ReminderTime1",
System.Data.OleDb.OleDbType.DBDate, 0,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "ReminderTime", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_Route",
System.Data.OleDb.OleDbType.VarWChar, 50,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "Route", System.Data.DataRowVersion.Original, Nothing))

Me.OleDbUpdateCommand1.Parameters.Add(New
System.Data.OleDb.OleDbParameter("Original_Route1",
System.Data.OleDb.OleDbType.VarWChar, 50,
System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0,
Byte), "Route", System.Data.DataRowVersion.Original, Nothing))

'

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