【单选题】使用SQL语句进行查询操作时,若希望查询结果中不出现重复元组,应在SELECT子句中使用( )关键字。
【单选题】It can be inferred from the passage that______.
A.
fire safety lessons should be aimed at American adults
B.
American children have not received enough education of fire safety lesson
C.
Japan is better equipped with fire facilities than the United States
D.
America's large population accounts for hight fire frequency
【单选题】What is this passage about?
B.
The new national fire safety campaign.
C.
The fire prevention handbook.
【简答题】Fire safety in family houses,_______ most fire deaths occur,is different to achieve. A.where B.which C.to which D.from what
【单选题】使用SQL语句进行查询操作时,若希望查询结果中不出现重复元组,应在select子句中使用()保留字。