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distinct對兩個字段去重 SQL語句如何去除重復記錄(不是用distinct去除重復的列哦?。??

SQL語句如何去除重復記錄(不是用distinct去除重復的列哦!)?-- DISTINCT 過濾重復行SELECT DISTINCT deptno, job FROM emp- UNION 過濾重復

SQL語句如何去除重復記錄(不是用distinct去除重復的列哦?。??

-- DISTINCT 過濾重復行SELECT DISTINCT deptno, job FROM emp- UNION 過濾重復值SELECT deptno, empno ,ename FROM emp WHERE deptno =30UNION SELECT deptno, empno ,ename FROM emp WHERE job = "MANAGER"