具體的分析函式的語法和函式列表見：
/*資料準備：
*以oracle樣例的sh模式為實驗資料
*建立實驗資料表：sales_fact
*/create table sales_fact as
select country_name country,country_subregion region,prod_name product,
calendar_year year,calendar_week_number week,
sum(amount_sold) sale,
sum(amount_sold *
(case
when mod(rownum,10)=0 then 1.4
when mod(rownum,5)=0 then 0.6
when mod(rownum,2)=0 then 0.9
when mod(rownum,2)=1 then 1.2
else 1 end)
) receipts
from sales,times,customers,countries,products
where sales.time_id =times.time_id and
sales.prod_id =products.prod_id and
sales.cust_id =customers.cust_id and
customers.country_id=countries.country_id
group by country_name, country_subregion,prod_name ,calendar_year, calendar_week_number;
---實驗一：聚合函式
/*1、獲取到目前為止的累積消費額；
*2、獲取前後五周內的最大消費額；
*/----獲取到目前為止的累積消費額；
select year,week,sale,
sum(sale)over
(partition by year
order by week
rows between unbounded preceding and current row) cumulate_sum---計算區間為年初到當前
from sales_fact
where product ='xtend memory' and country ='australia' and week between 1 and 3 and year in (1998,1999)
order by year,week;
-----實驗結果
-year-week-sale-cumulate_sum
1998 1 58.15 58.15
1998 2 29.39 87.54
1998 3 29.49 117.03
1999 1 53.52 53.52
1999 3 94.6 148.12
---獲取前後五周內的最大消費額；
select year,week,sale,
sum(sale)over
(partition by year
order by week
rows between 2 preceding and 2 following) cumulate_sum---計算區間為當前行前兩周到當前行的後兩周
from sales_fact
where product ='xtend memory' and country ='australia' and week between 1 and 5 and year in (1998,1999)
order by year,week;
---實驗結果
-year-week-sale-cumulate_sum
1998 1 58.15 117.03
1998 2 29.39 146.52
1998 3 29.49 176.32
1998 4 29.49 118.17
1998 5 29.8 88.78
1999 1 53.52 188.62
1999 3 94.6 268.63
1999 4 40.5 268.63
1999 5 80.01 215.11
----實驗二：定位函式：lead(),lag(),first_value(),last_value(),nth_value()
/*實驗目的：
*1、獲取前一周的銷售量【使用lag()】；
*2、獲取下一周的銷售量【使用lead()】;
*3、獲取最大的銷售額和最小的銷售額【使用first_value()和last_value()】;
*4、獲取第二高的銷售量【使用nth_value()】；
***/
select year,week,sale,
lag(sale,1,sale)over
(partition by year
order by week) lag,----1、獲取前一周的銷售量；
lead(sale,1,sale)over
(partition by year
order by week) lead, ---2、獲取下一周的銷售量;
first_value(sale)over
(partition by year
order by sale desc
rows between unbounded preceding and unbounded following) max_sale ,---3、最大的銷售額
last_value(sale)over
(partition by year
order by sale desc
rows between unbounded preceding and unbounded following) min_sale,---3、最小的銷售額
nth_value(sale,2) over
(partition by year
order by sale desc
rows between unbounded preceding and unbounded following) second_sale---4、第二高的銷售量
from sales_fact
where product ='xtend memory' and country ='australia' and week between 1 and 3 and year in (1998,1999)
order by year,week;
---實驗結果：
-year-week-sale---lag---lead---max_sale-min_sale-second_sale
1998 1 58.15 58.15 29.39 58.15 29.39 29.49
1998 2 29.39 58.15 29.49 58.15 29.39 29.49
1998 3 29.49 29.39 29.49 58.15 29.39 29.49
1999 1 53.52 53.52 94.6 94.6 53.52 53.52
1999 3 94.6 53.52 94.6 94.6 53.52 53.52
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