ieve rows in a nonsequential fashion (e.g.,
      backward). Depending upon the complexity of the query's
      execution plan, specifying <TT
CLASS="LITERAL"
>SCROLL</TT
> might impose
      a performance penalty on the query's execution time.
      <TT
CLASS="LITERAL"
>NO SCROLL</TT
> specifies that the cursor cannot be
      used to retrieve rows in a nonsequential fashion.  The default is to
      allow scrolling in some cases; this is not the same as specifying
      <TT
CLASS="LITERAL"
>SCROLL</TT
>. 