关系数据库的概念模式是 的集合。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30253' and id < 2447377 and id<>'2447377' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30253' and id > 2447377 and id<>'2447377' order by id asc limit 5