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distinct只對一列去重 SQL語句如何去除重復(fù)記錄(不是用distinct去除重復(fù)的列哦!)?

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

SQL語句如何去除重復(fù)記錄(不是用distinct去除重復(fù)的列哦?。?/h2>

-- DISTINCT 過濾重復(fù)行SELECT DISTINCT deptno, job FROM emp- UNION 過濾重復(fù)值SELECT deptno, empno ,ename FROM emp WHERE deptno =30UNION SELECT deptno, empno ,ename FROM emp WHERE job = "MANAGER"