计算机系统中除了硬件系统外，还必须有（ )0

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29906' and id < 2425449 and id<>'2425449' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29906' and id > 2425449 and id<>'2425449' order by id asc limit 5