1、sum(.) over .【功能】连续求和分析函数【参数】具体参示例【说明】Oracle 分析函数NC示例：select bdcode,sum(1) over(order by bdcode) aa from bd_bdinfo 【示例】1.原表信息： SQL break on deptno skip 1 - 为效果更明显，把不同部门的数据隔段显示。SQL select deptno,ename,sal2 from emp3 order by deptno;DEPTNO ENAME SAL- - -10 CLARK 2450KING 5000MILLER 130020 SMITH 800ADA
2、MS 1100FORD 3000SCOTT 3000JONES 297530 ALLEN 1600BLAKE 2850MARTIN 1250JAMES 950TURNER 1500WARD 12502.先来一个简单的，注意 over(.)条件的不同，使用 sum(sal) over (order by ename). 查询员工的薪水“连续”求和,注意 over (order by ename)如果没有 order by 子句，求和就不是“连续”的，放在一起，体会一下不同之处：SQL select deptno,ename,sal,2 sum(sal) over (order by ename)
3、 连续求和,3 sum(sal) over () 总和, - 此处 sum(sal) over () 等同于 sum(sal)4 100*round(sal/sum(sal) over (),4) “份额(%)“5 from emp6 /DEPTNO ENAME SAL 连续求和 总和 份额(%)- - - - - -20 ADAMS 1100 1100 29025 3.7930 ALLEN 1600 2700 29025 5.5130 BLAKE 2850 5550 29025 9.8210 CLARK 2450 8000 29025 8.4420 FORD 3000 11000 29025
4、 10.3430 JAMES 950 11950 29025 3.2720 JONES 2975 14925 29025 10.2510 KING 5000 19925 29025 17.2330 MARTIN 1250 21175 29025 4.3110 MILLER 1300 22475 29025 4.4820 SCOTT 3000 25475 29025 10.3420 SMITH 800 26275 29025 2.7630 TURNER 1500 27775 29025 5.1730 WARD 1250 29025 29025 4.313.使用子分区查出各部门薪水连续的总和。注意
5、按部门分区。注意 over(.)条件的不同，sum(sal) over (partition by deptno order by ename) 按部门“连续”求总和sum(sal) over (partition by deptno) 按部门求总和sum(sal) over (order by deptno，ename) 不按部门“连续”求总和sum(sal) over () 不按部门，求所有员工总和，效果等同于 sum(sal)。SQL select deptno,ename,sal,2 sum(sal) over (partition by deptno order by ename)
6、部门连续求和,-各部门的薪水“连续“求和3 sum(sal) over (partition by deptno) 部门总和, - 部门统计的总和，同一部门总和不变4 100*round(sal/sum(sal) over (partition by deptno),4) “部门份额(%)“,5 sum(sal) over (order by deptno,ename) 连续求和, -所有部门的薪水“连续“求和6 sum(sal) over () 总和, - 此处 sum(sal) over () 等同于sum(sal)，所有员工的薪水总和7 100*round(sal/sum(sal) ov
7、er (),4) “总份额(%)“8 from emp9 /DEPTNO ENAME SAL 部门连续求和 部门总和 部门份额(%) 连续求和 总和 总份额(%)- - - - - - - - -10 CLARK 2450 2450 8750 28 2450 29025 8.44KING 5000 7450 8750 57.14 7450 29025 17.23MILLER 1300 8750 8750 14.86 8750 29025 4.4820 ADAMS 1100 1100 10875 10.11 9850 29025 3.79FORD 3000 4100 10875 27.59 12
8、850 29025 10.34JONES 2975 7075 10875 27.36 15825 29025 10.25SCOTT 3000 10075 10875 27.59 18825 29025 10.34SMITH 800 10875 10875 7.36 19625 29025 2.7630 ALLEN 1600 1600 9400 17.02 21225 29025 5.51BLAKE 2850 4450 9400 30.32 24075 29025 9.82JAMES 950 5400 9400 10.11 25025 29025 3.27MARTIN 1250 6650 940
9、0 13.3 26275 29025 4.31TURNER 1500 8150 9400 15.96 27775 29025 5.17WARD 1250 9400 9400 13.3 29025 29025 4.314.来一个综合的例子，求和规则有按部门分区的，有不分区的例子SQL select deptno,ename,sal,sum(sal) over (partition by deptno order by sal) dept_sum,2 sum(sal) over (order by deptno,sal) sum3 from emp;DEPTNO ENAME SAL DEPT_SU
10、M SUM- - - - -10 MILLER 1300 1300 1300CLARK 2450 3750 3750KING 5000 8750 875020 SMITH 800 800 9550ADAMS 1100 1900 10650JONES 2975 4875 13625SCOTT 3000 10875 19625FORD 3000 10875 1962530 JAMES 950 950 20575WARD 1250 3450 23075MARTIN 1250 3450 23075TURNER 1500 4950 24575ALLEN 1600 6550 26175BLAKE 2850
11、 9400 290255.来一个逆序的，即部门从大到小排列，部门里各员工的薪水从高到低排列，累计和的规则不变。SQL select deptno,ename,sal,2 sum(sal) over (partition by deptno order by deptno desc,sal desc) dept_sum,3 sum(sal) over (order by deptno desc,sal desc) sum4 from emp;DEPTNO ENAME SAL DEPT_SUM SUM- - - - -30 BLAKE 2850 2850 2850ALLEN 1600 4450 4
12、450TURNER 1500 5950 5950WARD 1250 8450 8450MARTIN 1250 8450 8450JAMES 950 9400 940020 SCOTT 3000 6000 15400FORD 3000 6000 15400JONES 2975 8975 18375ADAMS 1100 10075 19475SMITH 800 10875 2027510 KING 5000 5000 25275CLARK 2450 7450 27725MILLER 1300 8750 290256.体会：在“. from emp;“后面不要加 order by 子句，使用的分析函
13、数的(partition by deptno order by sal)里已经有排序的语句了，如果再在句尾添加排序子句，一致倒罢了，不一致，结果就令人费劲了。如：SQL select deptno,ename,sal,sum(sal) over (partition by deptno order by sal) dept_sum,2 sum(sal) over (order by deptno,sal) sum3 from emp4 order by deptno desc;DEPTNO ENAME SAL DEPT_SUM SUM- - - - -30 JAMES 950 950 20575WARD 1250 3450 23075MARTIN 1250 3450 23075TURNER 1500 4950 24575ALLEN 1600 6550 26175BLAKE 2850 9400 2902520 SMITH 800 800 9550ADAMS 1100 1900 10650JONES 2975 4875 13625SCOTT 3000 10875 19625FORD 3000 10875 1962510 MILLER 1300 1300 1300CLARK 2450 3750 3750KING 5000 8750 8750
