电子邮件使用的传输协议是（28)。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29745' and id < 2415140 and id<>'2415140' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29745' and id > 2415140 and id<>'2415140' order by id asc limit 5