设数据集合为D=丨1，2, 3, 4, 5丨。下列数据结构DS= (D，R)中一定为非线性结构的是（

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SQL Error: select id,body,options from ***_enewstiku where sourceid='28854' and id < 2351106 and id<>'2351106' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='28854' and id > 2351106 and id<>'2351106' order by id asc limit 5