（）表示了对象间“is part of”的关系。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30195' and id < 2447140 and id<>'2447140' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30195' and id > 2447140 and id<>'2447140' order by id asc limit 5