本文探讨了在SQL中如何正确使用DELETE语句从SALES表中删除与特定促销活动相关的记录。通过三个有效的DELETE语句示例，展示了如何根据PROMOTIONS表中的PROMO_NAME值来定位并删除SALES表中的行。这些例子涵盖了使用子查询和IN子句的不同方法。
3.choose three
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 three DELETE statements are valid?
A) 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');
B) DELETE
FROM sales
WHERE 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');
C) DELETE
FROM sales
WHERE 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：ACD
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