三孔插座上哪个孔是火线？（ ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30395' and id < 2457172 and id<>'2457172' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30395' and id > 2457172 and id<>'2457172' order by id asc limit 5