Puede crear un pronóstico simple usando REGR funciones de regresión lineal.
--Ordinary least squares forecast for each customer for the next year.
select
cust_id,
max(year) +1 forecast_year,
-- y = mx+b
regr_slope(revenue, year)
* (max(year) + 1)
+ regr_intercept(revenue, year) forecasted_revenue
from customer_data
group by cust_id;
CUST_ID FORECAST_YEAR FORECASTED_REVENUE
------- ------------- ------------------
1 2018 730868
2 2018 50148
4 2018 7483
3 2018 -9920
A continuación se muestra el esquema de muestra. O puede usar este SQLFiddle .
create table customer_data
(
cust_id number,
year number,
revenue number
);
insert into customer_data
select 1, 2016, 679862 from dual union all
select 1, 2017, 705365 from dual union all
select 2, 2016, 51074 from dual union all
select 2, 2017, 50611 from dual union all
select 3, 2016, 190706 from dual union all
select 3, 2017, 90393 from dual union all
select 4, 2016, 31649 from dual union all
select 4, 2017, 19566 from dual;
El REGR
La función trata con pares de números, no entiende las reglas comerciales como "los ingresos no pueden ser inferiores a 0". Si desea restringir las previsiones para que permanezcan siempre en 0 o más, un CASE
expresión puede ayudar:
--Forecasted revenue, with minimum forecast of 0.
select cust_id, forecast_year,
case when forecasted_revenue < 0 then 0 else forecasted_revenue end forecasted_revenue
from
(
--Ordinary least squares forecast for each customer for the next year.
select
cust_id,
max(year) +1 forecast_year,
-- y = mx+b
regr_slope(revenue, year)
* (max(year) + 1)
+ regr_intercept(revenue, year) forecasted_revenue
from customer_data
group by cust_id
);
CUST_ID FORECAST_YEAR FORECASTED_REVENUE
------- ------------- ------------------
1 2018 730868
2 2018 50148
4 2018 7483
3 2018 0