SQL50题草仔细一想其实完全没怎么写过SQL语句查询1757. 可回收且低脂的产品SELECT p.product_id FROM Products AS p WHERE p.low_fats = 'Y' AND p.recyclable = 'Y' ;注意代码规范，比如关键字大写，合适的换行等584. 寻找用户推荐人SELECT c.name FROM Customer AS c WHERE c.referee_id != 2 OR c.referee_id IS null ;考虑到id可能为null的情况595. 大的国家SELECT name,population,area FROM World WHERE population>=25000000 OR area>=3000000 ;1148. 文章浏览 ISELECT DISTINCT author_id AS id FROM Views WHERE viewer_id = author_id ORDER BY author_id ASC;DISTINCT关键字可以起到去重的效果，会在根据条件查询结束后，删
punkginger
本质酒鬼
