下列哪一项不是带传动的优点?() ["无噪声","结构简单","有准确的传动比","能缓和冲击和振动"]
小车跟随列车后面推行时,应与列车尾部保持大于()的距离。 ["300m","400m","500m","800m"]
以下不属于悬挂系统故障内容的是()。 ["轮毂轴承损坏","前减振器漏油","后减振器弹簧损伤","后减振器漏油"]
在数据库设计中,() ["ER图用来描述关系模式","关系模式属于概念数据模型","全局视图也被称为模式","UML专门用于概念数据库设计"]
根据系统示例用户数据库提供的pubs表,阅读下列程序,说明其功能。 USE pubs GO WHILE (SELECT AVG(price) FROM titles) < $30 BEGIN UPDATE titles SET price = price * 2 SELECT MAX(price) FROM titles IF (SELECT MAX(price) FROM titles) > $50 BREAK ELSE CONTINUE END PRINT ‘Too much for the market to bear’
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