The query divides the current month’s sales amount by the previous month’s sales amount
SQL> CREATE TABLE all_sales (
2 year INTEGER,
3 month INTEGER,
4 prd_type_id INTEGER,
5 emp_id INTEGER ,
6 amount NUMBER(8, 2)
7 );
Table created.
SQL>
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,1 ,1 ,21 ,16034.84);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,2 ,1 ,21 ,15644.65);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,3 ,2 ,21 ,20167.83);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,4 ,2 ,21 ,25056.45);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,5 ,2 ,21 ,NULL);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,6 ,1 ,21 ,15564.66);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,7 ,1 ,21 ,15644.65);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,8 ,1 ,21 ,16434.82);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,9 ,1 ,21 ,19654.57);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,10 ,1 ,21 ,21764.19);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,11 ,1 ,21 ,13026.73);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2006,12 ,2 ,21 ,10034.64);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,1 ,2 ,22 ,16634.84);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,1 ,2 ,21 ,26034.84);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,2 ,1 ,21 ,12644.65);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,3 ,1 ,21 ,NULL);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,4 ,1 ,21 ,25026.45);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,5 ,1 ,21 ,17212.66);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,6 ,1 ,21 ,15564.26);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,7 ,2 ,21 ,62654.82);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,8 ,2 ,21 ,26434.82);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,9 ,2 ,21 ,15644.65);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,10 ,2 ,21 ,21264.19);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,11 ,1 ,21 ,13026.73);
1 row created.
SQL> insert into all_sales (YEAR,MONTH,PRD_TYPE_ID,EMP_ID,AMOUNT)
2 values(2005,12 ,1 ,21 ,10032.64);
1 row created.
SQL>
SQL> select * from all_sales;
YEAR MONTH PRD_TYPE_ID EMP_ID AMOUNT
---------- ---------- ----------- ---------- ----------
2006 1 1 21 16034.84
2006 2 1 21 15644.65
2006 3 2 21 20167.83
2006 4 2 21 25056.45
2006 5 2 21
2006 6 1 21 15564.66
2006 7 1 21 15644.65
2006 8 1 21 16434.82
2006 9 1 21 19654.57
2006 10 1 21 21764.19
2006 11 1 21 13026.73
2006 12 2 21 10034.64
2005 1 2 22 16634.84
2005 1 2 21 26034.84
2005 2 1 21 12644.65
2005 3 1 21
2005 4 1 21 25026.45
2005 5 1 21 17212.66
2005 6 1 21 15564.26
2005 7 2 21 62654.82
2005 8 2 21 26434.82
2005 9 2 21 15644.65
2005 10 2 21 21264.19
2005 11 1 21 13026.73
2005 12 1 21 10032.64
25 rows selected.
SQL>
SQL>
SQL> --The query divides the current months sales amount by the previous months sales amount
SQL>
SQL> SELECT
2 month, SUM(amount) AS month_amount,
3 SUM(amount)/FIRST_VALUE(SUM(amount)) OVER
4 (ORDER BY month ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING)
5 AS curr_div_prev,
6 SUM(amount)/LAST_VALUE(SUM(amount)) OVER
7 (ORDER BY month ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING)
8 AS curr_div_next
9 FROM all_sales
10 GROUP BY month
11 ORDER BY month;
MONTH MONTH_AMOUNT CURR_DIV_PREV CURR_DIV_NEXT
---------- ------------ ------------- -------------
1 58704.52 1 2.07514926
2 28289.3 .481893047 1.40269429
3 20167.83 .712913716 .402688942
4 50082.9 2.48330633 2.90965487
5 17212.66 .343683373 .552947548
6 31128.92 1.8084898 .397562333
7 78299.47 2.51532883 1.82645504
8 42869.64 .547508687 1.21446423
9 35299.22 .823408361 .820370648
10 43028.38 1.21896121 1.65154187
11 26053.46 .605494792 1.2983055
12 20067.28 .77023474 1
12 rows selected.
SQL>
SQL>
SQL> drop table all_sales;
Table dropped.
SQL>
SQL>