摘要：
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摘要：
1、列出至少有一个员工的所有部门名称。SELECT D.DNAME,COUNT(E.EMPNO) FROM EMP E,DEPT D WHERE E.DEPTNO(+) = D.DEPTNO GROUP BY D.DNAME HAVING COUNT(E.EMPNO)>0;SELECT D.DNAM 阅读全文