Dialogs must set the help context in the createDialogArea method (to provide context-sensitive help for the dialog itself).
EditDriverDialog (in org.eclipse.datatools.connectivity.internal.ui.dialogs) implements the createDialogArea method like this:
    protected Control createDialogArea(Composite parent) {
        getShell().setData( HelpUtil.CONTEXT_PROVIDER_KEY, this);
        HelpUtil.setHelp( getShell(),
            HelpUtil.getContextId(IHelpConstants.CONTEXT_ID_EDIT_DRIVER_DIALOG,
            ConnectivityUIPlugin.getDefault().getBundle().getSymbolicName()));
       ...
    }
        To provide more granular help, at a lower level in the dialog, the dialog could call setHelp, with a unique help context for each control in the dialog.
The string passed to the setHelp method is actually an abstract helpKey constant, whose property key is mapped to a concrete help context ID string by the ContextProviderDelegate.
All helpKey constant strings must be declared in an interface class.