Oracle分页话语与性能

Oracle分页语句与性能
olts_trade.trd_item表共有1665条数据，使用sql developer进行性能分析(解释计划)。
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    select * from olts_trade.trd_item where n_id in (        select n_id from (            select rownum rownum_,n_id from (                select n_ID from olts_trade.trd_item            ) where rownum <= 100        ) where rownum_ >= 90    )