y
    plan is simple enough that no extra overhead is needed to support
    it. However, application developers are advised not to rely on
    using backward fetches from a cursor that has not been created
    with <TT
CLASS="LITERAL"
>SCROLL</TT
>.  If <TT
CLASS="LITERAL"
>NO SCROLL</TT
> is
    specified, then backward fetches are disallowed in any case.
   </P
><P
>    Backward fetches are also disallowed when the query
    includes <TT
CLASS="LITERAL"
>FOR UPDATE</TT
> or <TT
CLASS="LITERAL"
>FOR SHARE<