ORACLE分析函式手冊二(轉)

REGR_ (Linear Regression) Functions 功能描述：這些線性迴歸函式適合最小二乘法迴歸線，有9個不同的迴歸函式可使用。 REGR_SLOPE：返回斜率，等於COVAR_POP(expr1, expr2) / VAR_POP(expr2) REGR_INTERCEPT：返回迴歸線的y截距，等於 AVG(expr1) - REGR_SLOPE(expr1, expr2) * AVG(expr2) REGR_COUNT：返回用於填充迴歸線的非空數字對的數目 REGR_R2：返回迴歸線的決定係數，計算式為： If VAR_POP(expr2) = 0 then return NULL If VAR_POP(expr1) = 0 and VAR_POP(expr2) != 0 then return 1 If VAR_POP(expr1) > 0 and VAR_POP(expr2 != 0 then return POWER(CORR(expr1,expr),2) REGR_AVGX：計算迴歸線的自變數(expr2)的平均值，去掉了空對(expr1, expr2)後，等於AVG(expr2) REGR_AVGY：計算迴歸線的應變數(expr1)的平均值，去掉了空對(expr1, expr2)後，等於AVG(expr1) REGR_SXX： 返回值等於REGR_COUNT(expr1, expr2) * VAR_POP(expr2) REGR_SYY： 返回值等於REGR_COUNT(expr1, expr2) * VAR_POP(expr1) REGR_SXY: 返回值等於REGR_COUNT(expr1, expr2) * COVAR_POP(expr1, expr2)（下面的例子都是在SH使用者下完成的）SAMPLE 1：下例計算1998年最後三個星期中兩種產品（260和270）在週末的銷售量中已開發票數量和總數量的累積斜率和迴歸線的截距SELECT t.fiscal_month_number "Month", t.day_number_in_month "Day", REGR_SLOPE(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_month_desc, t.day_number_in_month) AS CUM_SLOPE, REGR_INTERCEPT(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_month_desc, t.day_number_in_month) AS CUM_ICPT FROM sales s, times tWHERE s.time_id = t.time_id AND s.prod_id IN (270, 260) AND t.fiscal_year=1998 AND t.fiscal_week_number IN (50, 51, 52) AND t.day_number_in_week IN (6,7) ORDER BY t.fiscal_month_desc, t.day_number_in_month; Month Day CUM_SLOPE CUM_ICPT---------- ---------- ---------- ---------- 12 12 -68 1872 12 12 -68 1872 12 13 -20.244898 1254.36735 12 13 -20.244898 1254.36735 12 19 -18.826087 1287 12 20 62.4561404 125.28655 12 20 62.4561404 125.28655 12 20 62.4561404 125.28655 12 20 62.4561404 125.28655 12 26 67.2658228 58.9712313 12 26 67.2658228 58.9712313 12 27 37.5245541 284.958221 12 27 37.5245541 284.958221 12 27 37.5245541 284.958221SAMPLE 2：下例計算1998年4月每天的累積交易數量SELECT UNIQUE t.day_number_in_month, REGR_COUNT(s.amount_sold, s.quantity_sold) OVER (PARTITION BY t.fiscal_month_number ORDER BY t.day_number_in_month) "Regr_Count"FROM sales s, times tWHERE s.time_id = t.time_id AND t.fiscal_year = 1998 AND t.fiscal_month_number = 4;DAY_NUMBER_IN_MONTH Regr_Count------------------- ---------- 1 825 2 1650 3 2475 4 3300... 26 21450 30 22200SAMPLE 3：下例計算1998年每月銷售量中已開發票數量和總數量的累積迴歸線決定係數SELECT t.fiscal_month_number, REGR_R2(SUM(s.amount_sold), SUM(s.quantity_sold)) OVER (ORDER BY t.fiscal_month_number) "Regr_R2" FROM sales s, times t WHERE s.time_id = t.time_id AND t.fiscal_year = 1998 GROUP BY t.fiscal_month_number ORDER BY t.fiscal_month_number;FISCAL_MONTH_NUMBER Regr_R2------------------- ---------- 1 2 1 3 .927372984 4 .807019972 5 .932745567 6 .94682861 7 .965342011 8 .955768075 9 .959542618 10 .938618575 11 .880931415 12 .882769189SAMPLE 4：下例計算1998年12月最後兩週產品260的銷售量中已開發票數量和總數量的累積平均值SELECT t.day_number_in_month, REGR_AVGY(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_month_desc, t.day_number_in_month) "Regr_AvgY", REGR_AVGX(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_month_desc, t.day_number_in_month) "Regr_AvgX" FROM sales s, times t WHERE s.time_id = t.time_id AND s.prod_id = 260 AND t.fiscal_month_desc = @#1998-12@# AND t.fiscal_week_number IN (51, 52) ORDER BY t.day_number_in_month;DAY_NUMBER_IN_MONTH Regr_AvgY Regr_AvgX------------------- ---------- ---------- 14 882 24.5 14 882 24.5 15 801 22.25 15 801 22.25 16 777.6 21.6 18 642.857143 17.8571429 18 642.857143 17.8571429 20 589.5 16.375 21 544 15.1111111 22 592.363636 16.4545455 22 592.363636 16.4545455 24 553.846154 15.3846154 24 553.846154 15.3846154 26 522 14.5 27 578.4 16.0666667SAMPLE 5：下例計算產品260和270在1998年2月週末銷售量中已開發票數量和總數量的累積REGR_SXY, REGR_SXX, and REGR_SYY統計值SELECT t.day_number_in_month, REGR_SXY(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_year, t.fiscal_month_desc) "Regr_sxy", REGR_SYY(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_year, t.fiscal_month_desc) "Regr_syy", REGR_SXX(s.amount_sold, s.quantity_sold) OVER (ORDER BY t.fiscal_year, t.fiscal_month_desc) "Regr_sxx"FROM sales s, times tWHERE s.time_id = t.time_id AND prod_id IN (270, 260) AND t.fiscal_month_desc = @#1998-02@# AND t.day_number_in_week IN (6,7)ORDER BY t.day_number_in_month;DAY_NUMBER_IN_MONTH Regr_sxy Regr_syy Regr_sxx------------------- ---------- ---------- ---------- 1 18870.4 2116198.4 258.4 1 18870.4 2116198.4 258.4 1 18870.4 2116198.4 258.4 1 18870.4 2116198.4 258.4 7 18870.4 2116198.4 258.4 8 18870.4 2116198.4 258.4 14 18870.4 2116198.4 258.4 15 18870.4 2116198.4 258.4 21 18870.4 2116198.4 258.4 22 18870.4 2116198.4 258.4

ROW_NUMBER 功能描述：返回有序組中一行的偏移量，從而可用於按特定標準排序的行號。SAMPLE：下例返回每個員工再在每個部門中按員工號排序後的順序號

SELECT department_id, last_name, employee_id, ROW_NUMBER() OVER (PARTITION BY department_id ORDER BY employee_id) AS emp_id FROM employeesWHERE department_id < 50;DEPARTMENT_ID LAST_NAME EMPLOYEE_ID EMP_ID------------- ------------------------- ----------- ---------- 10 Whalen 200 1 20 Hartstein 201 1 20 Fay 202 2 30 Raphaely 114 1 30 Khoo 115 2 30 Baida 116 3 30 Tobias 117 4 30 Himuro 118 5 30 Colmenares 119 6 40 Mavris 203 1

STDDEV 功能描述：計算當前行關於組的標準偏離。（Standard Deviation）

SAMPLE：下例返回部門30按僱傭日期排序的薪水值的累積標準偏離SELECT last_name, hire_date,salary, STDDEV(salary) OVER (ORDER BY hire_date) "StdDev" FROM employees WHERE department_id = 30;LAST_NAME HIRE_DATE SALARY StdDev------------------------- ---------- ---------- ----------Raphaely 07-12月-94 11000 0Khoo 18-5月 -95 3100 5586.14357Tobias 24-7月 -97 2800 4650.0896Baida 24-12月-97 2900 4035.26125Himuro 15-11月-98 2600 3649.2465Colmenares 10-8月 -99 2500 3362.58829S

TDDEV_POP 功能描述：該函式計算總體標準偏離，並返回總體變數的平方根，其返回值與VAR_POP函式的平方根相同。（Standard Deviation－Population）SAMPLE：下例返回部門20、30、60的薪水值的總體標準偏差SELECT department_id, last_name, salary, STDDEV_POP(salary) OVER (PARTITION BY department_id) AS pop_std FROM employeesWHERE department_id in (20,30,60);DEPARTMENT_ID LAST_NAME SALARY POP_STD------------- ------------------------- ---------- ---------- 20 Hartstein 13000 3500 20 Fay 6000 3500 30 Raphaely 11000 3069.6091 30 Khoo 3100 3069.6091 30 Baida 2900 3069.6091 30 Colmenares 2500 3069.6091 30 Himuro 2600 3069.6091 30 Tobias 2800 3069.6091 60 Hunold 9000 1722.32401 60 Ernst 6000 1722.32401 60 Austin 4800 1722.32401 60 Pataballa 4800 1722.32401 60 Lorentz 4200 1722.32401

STDDEV_SAMP 功能描述： 該函式計算累積樣本標準偏離，並返回總體變數的平方根，其返回值與VAR_POP函式的平方根相同。（Standard Deviation－Sample）

SAMPLE：下例返回部門20、30、60的薪水值的樣本標準偏差SELECT department_id, last_name, hire_date, salary, STDDEV_SAMP(salary) OVER (PARTITION BY department_id ORDER BY hire_date ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS cum_sdev FROM employeesWHERE department_id in (20,30,60);DEPARTMENT_ID LAST_NAME HIRE_DATE SALARY CUM_SDEV------------- ------------------------- ---------- ---------- ---------- 20 Hartstein 17-2月 -96 13000 20 Fay 17-8月 -97 6000 4949.74747 30 Raphaely 07-12月-94 11000 30 Khoo 18-5月 -95 3100 5586.14357 30 Tobias 24-7月 -97 2800 4650.0896 30 Baida 24-12月-97 2900 4035.26125 30 Himuro 15-11月-98 2600 3649.2465 30 Colmenares 10-8月 -99 2500 3362.58829 60 Hunold 03-1月 -90 9000 60 Ernst 21-5月 -91 6000 2121.32034 60 Austin 25-6月 -97 4800 2163.33077 60 Pataballa 05-2月 -98 4800 1982.42276 60 Lorentz 07-2月 -99 4200 1925.61678

SUM 功能描述：該函式計算組中表示式的累積和。

SAMPLE：下例計算同一經理下員工的薪水累積值SELECT manager_id, last_name, salary, SUM (salary) OVER (PARTITION BY manager_id ORDER BY salary RANGE UNBOUNDED PRECEDING) l_csum FROM employees WHERE manager_id in (101,103,108);MANAGER_ID LAST_NAME SALARY L_CSUM---------- ------------------------- ---------- ---------- 101 Whalen 4400 4400 101 Mavris 6500 10900 101 Baer 10000 20900 101 Greenberg 12000 44900 101 Higgins 12000 44900 103 Lorentz 4200 4200 103 Austin 4800 13800 103 Pataballa 4800 13800 103 Ernst 6000 19800 108 Popp 6900 6900 108 Sciarra 7700 14600 108 Urman 7800 22400 108 Chen 8200 30600 108 Faviet 9000 39600

VAR_POP功能描述：（Variance Population）該函式返回非空集合的總體變數（忽略null），VAR_POP進行如下計算： (SUM(expr2) - SUM(expr)2 / COUNT(expr)) / COUNT(expr)

SAMPLE：下例計算1998年每月銷售的累積總體和樣本變數（本例在SH使用者下執行）SELECT t.calendar_month_desc, VAR_POP(SUM(s.amount_sold)) OVER (ORDER BY t.calendar_month_desc) "Var_Pop", VAR_SAMP(SUM(s.amount_sold)) OVER (ORDER BY t.calendar_month_desc) "Var_Samp" FROM sales s, times tWHERE s.time_id = t.time_id AND t.calendar_year = 1998GROUP BY t.calendar_month_desc;CALENDAR Var_Pop Var_Samp-------- ---------- ----------1998-01 01998-02 6.1321E+11 1.2264E+121998-03 4.7058E+11 7.0587E+111998-04 4.6929E+11 6.2572E+111998-05 1.5524E+12 1.9405E+121998-06 2.3711E+12 2.8453E+121998-07 3.7464E+12 4.3708E+121998-08 3.7852E+12 4.3260E+121998-09 3.5753E+12 4.0222E+121998-10 3.4343E+12 3.8159E+121998-11 3.4245E+12 3.7669E+121998-12 4.8937E+12 5.3386E+12

VAR_SAMP 功能描述：（Variance Sample）該函式返回非空集合的樣本變數（忽略null），VAR_POP進行如下計算： (SUM(expr*expr)-SUM(expr)*SUM(expr)/COUNT(expr))/(COUNT(expr)-1)SAMPLE：下例計算1998年每月銷售的累積總體和樣本變數SELECT t.calendar_month_desc, VAR_POP(SUM(s.amount_sold)) OVER (ORDER BY t.calendar_month_desc) "Var_Pop", VAR_SAMP(SUM(s.amount_sold)) OVER (ORDER BY t.calendar_month_desc) "Var_Samp" FROM sales s, times tWHERE s.time_id = t.time_id AND t.calendar_year = 1998GROUP BY t.calendar_month_desc;CALENDAR Var_Pop Var_Samp-------- ---------- ----------1998-01 01998-02 6.1321E+11 1.2264E+121998-03 4.7058E+11 7.0587E+111998-04 4.6929E+11 6.2572E+111998-05 1.5524E+12 1.9405E+121998-06 2.3711E+12 2.8453E+121998-07 3.7464E+12 4.3708E+121998-08 3.7852E+12 4.3260E+121998-09 3.5753E+12 4.0222E+121998-10 3.4343E+12 3.8159E+121998-11 3.4245E+12 3.7669E+121998-12 4.8937E+12 5.3386E+12

VARIANCE 功能描述：該函式返回表示式的變數，Oracle計算該變數如下： 如果表示式中行數為1，則返回0 如果表示式中行數大於1，則返回VAR_SAMP

SAMPLE：下例返回部門30按僱傭日期排序的薪水值的累積變化SELECT last_name, salary, VARIANCE(salary) OVER (ORDER BY hire_date) "Variance" FROM employees WHERE department_id = 30;LAST_NAME SALARY Variance------------------------- ---------- ----------Raphaely 11000 0Khoo 3100 31205000Tobias 2800 21623333.3Baida 2900 16283333.3Himuro 2600 13317000Colmenares 2500 11307000

來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/756652/viewspace-242343/，如需轉載，請註明出處，否則將追究法律責任。