关于oracle 开窗函数--1
一.OVER
1.SQL> SELECT deptno,ename,sal FROM emp ORDER BY deptno,ename;


    DEPTNO ENAME             SAL
---------- ---------- ----------
        10 CLARK            2450
        10 KING             5000
        10 MILLER           1300
        20 FORD             3000
        20 JONES            2975
        20 SMITH             800
        30 ALLEN            1600
        30 BLAKE            2850
        30 JAMES             950
        30 MARTIN           1250
        30 TURNER           1500
        30 WARD             1250


已选择12行。


2.SQL> SELECT deptno,ename,sal,
  2  SUM(sal) OVER(ORDER BY ename) 连续求和,
  3  SUM(sal) OVER() 总和, --等效于SUM(sal)
  4  100*ROUND(sal/SUM(sal) OVER(),4) "份额(%)"
  5  FROM emp;


    DEPTNO ENAME             SAL   连续求和       总和    份额(%)
---------- ---------- ---------- ---------- ---------- ----------
        30 ALLEN            1600       1600      24925       6.42
        30 BLAKE            2850       4450      24925      11.43
        10 CLARK            2450       6900      24925       9.83
        20 FORD             3000       9900      24925      12.04
        30 JAMES             950      10850      24925       3.81
        20 JONES            2975      13825      24925      11.94
        10 KING             5000      18825&nbs