一般按信噪比10∶1来确定的是

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='30368' and id < 2454698 and id<>'2454698' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30368' and id > 2454698 and id<>'2454698' order by id asc limit 5