定义关系的主码意味着主码属性（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30102' and id < 2437047 and id<>'2437047' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30102' and id > 2437047 and id<>'2437047' order by id asc limit 5