Oracle paging SQL

Select * from
(Select a. *, rownum R
From
-- The SQL here can be changed to the SQL statement you actually want to parse.
(Select * from articles
Order by pubtime DESC
)
-- Use the set returned by the preceding SQL statement, and use rownum to compare, so that rownum will
-- The first item of a collection starts to be computed, so this is the first 100 items
Where rownum <= 100
) B
-- The B set has a total of A sets and R (rownum) resources, which are larger than 90th bytes.
Where R> 90;