为了确保相关表之间数据的一致性,需要设置______。
参考答案:参照完整性
Mr. Green ______ for America the day after tomorrow. [ ]
A. left
B. leaves
C. is leaving
D. is going to leave
滚筒边缘应高出最外一层钢丝绳,高出部分至少为钢丝绳直径的2.5倍。