摘要:        
`db`SELECT sal FROM emp ORDER BY sal;--选出薪水进行升序排列 SELECT DISTINCT sal FROM emp ORDER BY sal;--去重关键字diatinct 将sal挑出并且按照默认升序排序SELECT DISTINCT job,deptno    阅读全文
            
                posted @ 2020-03-21 21:46
Office2019
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