在数据流图中，O (椭圆）代表（）。 

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30195' and id < 2447064 and id<>'2447064' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30195' and id > 2447064 and id<>'2447064' order by id asc limit 5