摘要:1、查询“001”课程比“002”课程成绩高的所有学生的学号; select a.S# from (select s#,score from SC where C#=’001′) a,(select s#,score from SC where C#=’002′) b where a.score>b
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摘要:top: sql server: top MySQL: SELECT column_name(s) FROM table_name LIMIT number distinct: 返回唯一值 where 和 order by: order by 应放于where之后 空值检查 is null is n
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