zoukankan      html  css  js  c++  java
  • 使用oracle来计算方差及标准差

    /* Formatted on 5/24/2012 4:15:58 PM (QP5 v5.149.1003.31008) */
    SELECT deptno,
          ename,                     --st_name || ' ' || last_name employee_name,
          hiredate,
         sal,
           STDDEV (sal) OVER (PARTITION BY deptno ORDER BY hiredate) AS "STDDEV", --标准差
           STDDEV_SAMP (sal) OVER (PARTITION BY deptno ORDER BY hiredate)
              AS "STDDEV_SAMP",                                            --样本标准差
           VAR_POP (sal) OVER (PARTITION BY deptno ORDER BY hiredate)    说明:VAR_POP 为函数, sal为要求的数据列,  以‘deptno’为分组的根据,即满足这个条件下才进行方差的操作,最后根据‘hiredate’进行排序。
              AS "VAR_POP",                                                   --方差
           VAR_SAMP (sal) OVER (PARTITION BY deptno ORDER BY hiredate)
              AS "VAR_SAMP"                                                 --样本方差
      FROM scott.emp
     WHERE deptno IN (20);
     
     /* Formatted on 5/24/2012 4:15:58 PM (QP5 v5.149.1003.31008) */
    SELECT deptno,
           STDDEV (sal)  AS "STDDEV", --标准差
           STDDEV_SAMP (sal)
              AS "STDDEV_SAMP",                                            --样本标准差
           VAR_POP (sal)
              AS "VAR_POP",                                                   --方差
           VAR_SAMP (sal)
              AS "VAR_SAMP"                                                 --样本方差
      FROM scott.emp
    group  by deptno

  • 相关阅读:
    阿凯
    hlg神秘植物--矩阵快速幂
    poj1185炮兵阵地--状态dp
    该怎么办
    hlg2096---状态压缩dp
    这个世界

    第三篇
    LCT板子
    spoj COT
  • 原文地址:https://www.cnblogs.com/AdaLoong/p/5595054.html
Copyright © 2011-2022 走看看