SELECT EMPNO, ENAME, DEPTNO, SAL, --注意ROWS BETWEEN 1 preceding AND 1 following 是指当前行的上一行(rownum-1)到当前行的下辆行(rownum+2)的汇总 SUM(SAL) OVER(PARTITION BY DEPTNO ORDER BY ENAME ROWS BETWEEN 1 PRECEDING AND 2 FOLLOWING) max_sal FROM SCOTT.EMP; 运行结果: 二、理解over()...
over(order by sroce range between 5 preceding and 5 following):窗口范围为当前行数据幅度减5加5后的范围内的。 over(order by sroce rows between 5 preceding and 5 following):窗口范围为当前行前后各移动5行。 3、与over()函数结合的函数的介绍 (1)、查询每个班的第一名的成绩:如下 SELECT * FROM ...
1.2、开窗函数over()分析函数中的分组/排序/窗口开窗函数over()分析函数包含三个分析子句:分组子句(partition by), 排序子句(order by), 窗口子句(rows) 窗口就是分析函数分析时要处理的数据范围,就拿sum来说,它是sum窗口中的记录而不是整个分组中的记录,因此我们在想得到某个栏位的累计值时,我们需要把窗口指定...
min() over(partition by ... order by ...) sum() over(partition by ... order by ...) avg() over(partition by ... order by ...) first_value() over(partition by ... order by ...) last_value() over(partition by ... order by ...) lag() over(partition by ... order b...
就是说,对于aa=5的一行 ,sum为 5-1<=aa<=5+2 的和 对于aa=2来说 ,sum=1+2+2+2+3+4=14 ; 又如 对于aa=9 ,9-1<=aa<=9+2 只有9一个数,所以sum=9 ; 3:其它: over(order by salary rows between 2 preceding and 4 following) ...
对于aa=2来说 ,sum=1+2+2+2+3+4=14 ; 又如 对于aa=9 ,9-1<=aa<=9+2 只有9一个数,所以sum=9 ; 3:其它: over(order by salary rows between 2 preceding and 4 following) 每行对应的数据窗口是之前2行,之后4行 4:下面三条语句等效: ...
就是说,对于aa=5的一行 ,sum为 5-1<=aa<=5+2 的和 对于aa=2来说 ,sum=1+2+2+2+3+4=14 ; 又如 对于aa=9 ,9-1<=aa<=9+2 只有9一个数,所以sum=9 ; 3:其它: over(order by salary rows between 2 preceding and 4 following) ...
over(order by salary rows between unbounded preceding and unbounded following) 每行对应的数据窗口是从第一行到最后一行,等效: over(order by salary range between unbounded preceding and unbounded following) 等效 over(partition by null) sum(nid)over(partitionbyv1orderbynid)(2007-05-16 16:22:48) ...
SUM(id) OVER ( ORDER BY id ROWS BETWEEN 1 PRECEING AND 2 FOLLOWING ) 是取前1行到后2行的数据求和,分析: 当id=1时,前一行没数,,后二行是第3行,就是1到3行; 当id=3时,前一行是第2行,后二行是第5行,就是2到5行; (3)带有窗口子句 ...
SELECT column1, column2, SUM(column3) OVER (PARTITION BY column1) AS sum_total FROM table_name; ``` 在上面的查询中,SUM(column3) OVER (PARTITION BY column1)表示对column3列进行求和计算,并按column1列进行分区。结果将为每个不同的column1值返回一个独立的分区,并在每个分区内计算column3的总和。