Split date range into weeks in sql - sql

Question

Given a table called Project, I need the list of team_id's who won at least an award every week in last 3 months
launch_date team_id project_name
2019-01-01 123 A
2019-01-01 345 B
2019-01-01 357 C
2019-01-09 123 D
2019-01-08 345 E
2019-01-21 123 F
project_name award
A Y
B N
C Y
D Y
E N
F Y
last 3 months can be achieved with below where condition but how do i split the launch_date into weekly intervals
where launch_date >= sysdate - 90
With the given data, answer should be team id 123

Answer 1

In your sample data, You have only given 21 days of data instead of 3 months.
You can find out the total number of weeks and their week starting date which can then be compared with your table data to check if an award is won by the team for each week as follows:
SQL> --SAMPLE DATA
SQL> with teams (launch_date, team_id, project_name)
2 as
3 (SELECT DATE'2019-01-01', 123, 'A' FROM DUAL UNION ALL
4 SELECT DATE'2019-01-01', 345, 'B' FROM DUAL UNION ALL
5 SELECT DATE'2019-01-01', 357, 'C' FROM DUAL UNION ALL
6 SELECT DATE'2019-01-09', 123, 'D' FROM DUAL UNION ALL
7 SELECT DATE'2019-01-08', 345, 'E' FROM DUAL UNION ALL
8 SELECT DATE'2019-01-21', 123, 'F' FROM DUAL),
9 AWARDS(project_name, award)
10 AS
11 (SELECT 'A','Y' FROM DUAL UNION ALL
12 SELECT 'B','N' FROM DUAL UNION ALL
13 SELECT 'C','Y' FROM DUAL UNION ALL
14 SELECT 'D','Y' FROM DUAL UNION ALL
15 SELECT 'E','N' FROM DUAL UNION ALL
16 SELECT 'F','Y' FROM DUAL),
17 -- YOUR QUERY START FROM HERE
18 -- WITH
19 WKS(DT) AS
20 (SELECT DISTINCT TRUNC(DATE '2019-01-21' - LEVEL + 1, 'W')
21 FROM DUAL CONNECT BY LEVEL <= 21
22 )
23 SELECT T.TEAM_ID
24 FROM WKS W
25 LEFT JOIN TEAMS T ON W.DT = TRUNC(T.LAUNCH_DATE, 'W')
26 LEFT JOIN AWARDS A ON A.PROJECT_NAME = T.PROJECT_NAME
27 WHERE A.AWARD = 'Y'
28 GROUP BY T.TEAM_ID
29 HAVING COUNT(1) = ( SELECT COUNT(1) FROM WKS);
TEAM_ID
----------
123
SQL>
In WKS cte for 3 months data, You need to replace the
WKS(DT) AS
(SELECT DISTINCT TRUNC(DATE '2019-01-21' - LEVEL + 1, 'W')
FROM DUAL CONNECT BY LEVEL <= 21
)
with
WKS(DT) AS
( SELECT DISTINCT TRUNC(sysdate - LEVEL + 1, 'W')
FROM DUAL CONNECT BY LEVEL <= trunc(sysdate) - add_months(trunc(sysdate), -3
)