zoukankan      html  css  js  c++  java
  • OCP-1Z0-051-题目解析-第16题

    16. Evaluate the following query:
    SQL> SELECT promo_name  q'{'s start date was }'  promo_begin_date                           
    AS "Promotion Launches"
    FROM promotions;
    What would be the outcome of the above query?


    A. It produces an error because flower braces have been used.
    B. It produces an error because the data types are not matching.
    C. It executes successfully and introduces an   's at the end of each promo_name in the output.

    D. It executes successfully and displays the literal " {'s start date was } " for each row in the output.

    Answer: C

    题目解析:
    A:会产生一个错误,由于使用的花括号(错误,该处的花括号是Q-quote的表达式)
    B:会产生一个错误。由于数据类型不匹配(错误,无关选项)
    C:会正确运行。而且在每个promo_name后面加入一个's(正确,这是一个Q-quote的表达式)
    D: 会正确运行,而且在每行输出字符串{'s start date was }(错误)


    关于这道题的具体解答參照第13题:http://blog.csdn.net/wjx515628/article/details/35278889 
  • 相关阅读:
    JEECG开发总结
    ehcache集群的配置
    spring拦截器
    spring的基本配置
    kindeditor编辑器
    jQuery中的Ajax
    表单验证
    Python中的Random模块
    Open vSwitch FAQ (二)
    Open vSwitch FAQ (一)
  • 原文地址:https://www.cnblogs.com/clnchanpin/p/6816856.html
Copyright © 2011-2022 走看看