ocp-051-3

发布时间:2019-08-24 09:24:04编辑:auto阅读(1792)

    一、原题

    You need to extract details of those products in the SALES table where the PROD_ID column contains the string '_D123'.
    Which WHERE clause could be used in the SELECT statement to get the required output?
    A. WHERE prod_id LIKE '%_D123%' ESCAPE '_'
    B. WHERE prod_id LIKE '%\_D123%' ESCAPE '\'
    C. WHERE prod_id LIKE '%_D123%' ESCAPE '%_'
    D. WHERE prod_id LIKE '%\_D123%' ESCAPE '\_'

             答案 B

    二、题目翻译

         要从SALES表中提取出PROD_ID列包含'_D123'字符串的产品明细。
         下面哪一个WHERE条件子句可以获得所需的输出结果?

    三、题目解析
          ESCAPE子句为指定转译字符,因为'_'下画线在LIKE子句中指的是任意一个字符,所以需要把'_'下画线进行转义,转义字符设置为'\'。


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