If KEYSET_SIZE=0, the
                  entire cursor is keyset-driven.
               
 
               If you specify a value
                  greater than 0, that value indicates the number of rows within the
                  cursor that function as a keyset-driven cursor. When you scroll beyond
                  the bounds that KEYSET_SIZE= specifies, the cursor becomes dynamic
                  and new rows might be included in the cursor. This results in a new
                  keyset, where the cursor functions as a keyset-driven cursor again.
               
 
               When you specify a value
                  between 1 and the number of rows in the cursor, the cursor is considered
                  to be a mixed cursor. Part of the cursor functions as a keyset-driven
                  cursor, and another part of the cursor functions as a dynamic cursor.