The BookmarkDefault keyword in the Extended Property segment of the connect string controls whether the Provider creates rowsets with or without a bookmark column. OLE DB does not specify what the default behavior should be.
The Single-Tier "Lite" Edition OLE DB Provider for ODBC Data Sources includes a bookmark column by default.
It is not generally necessary to change this setting, but you can explicitly turn bookmarks on or off with an entry of the form:
BookmarkDefault = On BookmarkDefault = Off