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今天在做sql查询练习，查询单个表中的数据时遇到了查询结果相同的问题 SELECT * FROM hero WHERE grounding_date BETWEEN '2007-01-01' AND '2019-01-01'; sql1 SELECT * FROM hero WHERE grounding_date BETWEEN '20007-01-01' AND '2019-01-01';sql2 1sql1上架日期查询sql是中的20007是我无意间 ，天太冷多打出来的，结果我发现查询结果和200

sql练习题 练习查询和"01"号的同学学习的课程完全相同的其他同学的信息 SELECT s_id,s_name,s_birth,s_sex FROM student WHERE student.s_id in( SELECT s_id FROM score WHERE s_id!='01’AND c_id IN ( SELECT c_id FROM score WHERE s_id=‘01’) GROUP BY s_id HAVING COUNT() =(SELECT COUNT() FROM sc