Inserting and deleting records in a sorted file are problematic because the order
of records has to be maintained. To insert a new record, we must find the correct
position in the ordering for the record and then find space to insert it. If there is
sufficient space in the required page for the new record, then the single page can
be reordered and written back to disk. If this is not the case, then it would be necessary
to move one or more records on to the next page. Again, the next page may
have no free space and the records on this page must be moved, and so on.