Immediately before each update is applied, a dataset provider receives a BeforeUpdateRecord event. You can use this event to edit records before they are applied, similar to the way you can use the OnUpdateData event to edit entire delta packets. For example, the provider does not compare BLOB fields (such as memos) when checking for update conflicts. If you want to check for update errors involving BLOB fields, you can use the BeforeUpdateRecord event. 

In addition, you can use this event to apply updates yourself or to screen and reject updates. The BeforeUpdateRecord event handler lets you signal that an update has been handled already and should not be applied. The provider then skips that record, but does not count it as an update error. For example, this event provides a mechanism for applying updates to a stored procedure (which can't be updated automatically), allowing the provider to skip any automatic processing once the record is updated from within the event handler.