Write a BeforeUpdateRecord event handler to: 

Prepare individual record updates before they are applied to the database server. For example, you can insert additional changes into a record before it is updated or set the ProviderFlags property of the fields in the DeltaDS parameter to indicate how you want to identify the records that are to be updated or changed and which fields should be updated. 

Manually apply updates that the internal provider can't handle. For example, the provider can't generate the appropriate SQL when the data results from a multi-table join and more than one table must be updated. Write code in the event handler to apply the update and then set the Applied parameter to true so that the internal provider does not generate an error. 

Provider 

ApplyUpdates 

OnReconcileError 

ProviderFlags 

AfterUpdateRecord 

OnUpdateData 

OnUpdateError 

Intervening as Updates Are Applied 

Using Multiple Update Objects 

Using the BDE to Cache Updates 

Using Update Objects to Update a Dataset