OCP-1Z0-051-V9.02-168题

vike681

168. View the Exhibit and examine the description of SALES and PROMOTIONS tables.
You want to delete rows from the SALES table, where the PROMO_NAME column in the PROMOTIONS
table has either blowout sale or everyday low price as values.
Which DELETE statements are valid? (Choose all that apply.)
delete from sales
where promo_id=(select promo_id from promotions where)


A. DELETE FROM salesWHERE promo_id = (SELECT promo_id                  　　FROM promotions                  
　　WHERE promo_name = 'blowout sale')
　　AND promo_id = (SELECT promo_id                  
　　FROM promotions                  
　　WHERE promo_name = 'everyday low price');
　　B. DELETE FROM sales
　　WHERE promo_id = (SELECT promo_id                  
　　FROM promotions                  
　　WHERE promo_name = 'blowout sale')
　　OR promo_id = (SELECT promo_id                  
　　FROM promotions                  
　　WHERE promo_name = 'everyday low price');
　　
C. DELETE FROM salesWHERE promo_id IN (SELECT promo_id                   　　FROM promotions                  
　　WHERE promo_name = 'blowout sale'                  
　　OR promo_name = 'everyday low price');
　　D. DELETE FROM sales
　　WHERE promo_id IN (SELECT promo_id                  
　　FROM promotions                  
　　WHERE promo_name IN ('blowout sale','everyday low price'));
　　Answer: BCD
　　答案解析：
　　题意要求：从SALES表中删除行，条件为PROMOTIONS表中PROMO_NAM列的值为blowout sale或者everyday low price）
　　BCD这三个选项是等价的。
　　而A的where条件中的AND不满足题意要求。
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