PL/SQL 查询函数
求教各位大虾：我想在一张表中找到某一列上所有行记录的中位值，或者是所有行记录中95%的行值是多大，其实就是用来剔除表中某些行出现的异常值，但是我不知道这个异常值是多大。

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转载http://luobeng.blogbus.com/logs/36300419.html

Oracle/PLSQL: Median Function


In Oracle/PLSQL, the median function returns the median of an expression.

The syntax for the median function is:

median( expression ) [ OVER ( query partition clause ) ]



For example:

select median(salary)
from employees
where department = 'Marketing';


------解决方案--------------------
with tb as (
select '王' name,'数学' course, 88 score, '2011-11-30 18:11:00' time from dual union all
select '王1' , '数学', 78, '2011-11-30 18:11:00' from dual union all
select '王2' , '数学', 99, '2011-10-30 18:11:00' from dual union all
select '张' , '数学', 67, '2011-11-30 18:11:00' from dual 
) 
select median(score) as median from tb

MEDIAN
---------------------- 
83