How to get date difference and date from the below table - sql

Question

I have a table like this
Emplid
REQUEST_ID
Status
Status_Dttm
1234
1
New
02-Jun-2022 12.35.00.AM
1231
5
Draft
02-Jun-2022 12.30.00.AM
1234
1
In Progress
02-Jun-2022 12.47.00.AM
1234
1
Cancelled
02-Jun-2022 12.50.00.AM
1234
2
New
03-Jun-2022 12.47.00.AM
Trying to create a view with the fields as EMPLID,REQUEST_ID,REQUEST_DATE,NO_OF_DAYS_IN_NEW,IN_PROGRESS_SINCE,COMPLETED/CANCELLED DATE
Tried using this
SELECT MIN(emplid) AS emplid, request_id, MIN(status_dttm) AS request_date,
MAX(status) KEEP (DENSE_RANK LAST ORDER BY status_dttm) AS current_status
FROM sts_tbl
GROUP BY request_id
CASE WHEN (MAX(status) KEEP (DENSE_RANK LAST ORDER BY status_dttm)) = 'NEW' THEN
TRUNC(SYSDATE) - MIN(status_dttm)
END AS "No of Days in New"
CASE WHEN (MAX(status) KEEP (DENSE_RANK LAST ORDER BY status_dttm)) = 'In Progree' THEN
status_dttm
END AS "In Progress Since"
FROM sts_tbl
GROUP BY emplid,request_id
getting error as "Not a Group By expression"

Answer 1

You can use the LEAD analytic function to find the time of the next status change and then aggregate:
SELECT MIN(emplid) AS emplid,
request_id,
MIN(status_dttm) AS request_date,
SUM(CASE status WHEN 'New' THEN duration ELSE 0 END) AS no_of_days_in_new,
MIN(CASE status WHEN 'In Progress' THEN status_dttm END)
AS in_progress_since,
MAX(status) KEEP (DENSE_RANK LAST ORDER BY status_dttm)
AS current_status,
MIN(CASE WHEN status IN ('Completed', 'Cancelled') THEN status_dttm END)
AS completed_cancelled_date
FROM (
SELECT t.*,
LEAD(status_dttm, 1, SYSDATE) OVER (
PARTITION BY request_id ORDER BY status_dttm
) - status_dttm AS duration
FROM sts_tbl t
)
GROUP BY request_id
Which, for the sample data:
CREATE TABLE sts_tbl (Emplid, REQUEST_ID, Status, Status_Dttm) AS
SELECT 1234, 1, 'Open', DATE '2022-06-02' + INTERVAL '35' MINUTE FROM DUAL UNION ALL
SELECT 1231, 5, 'Draft', DATE '2022-06-02' + INTERVAL '30' MINUTE FROM DUAL UNION ALL
SELECT 1234, 1, 'In Progress', DATE '2022-06-02' + INTERVAL '47' MINUTE FROM DUAL UNION ALL
SELECT 1234, 1, 'Cancelled', DATE '2022-06-02' + INTERVAL '50' MINUTE FROM DUAL UNION ALL
SELECT 1234, 2, 'New', DATE '2022-06-03' + INTERVAL '47' MINUTE FROM DUAL;
Outputs:
EMPLID
REQUEST_ID
REQUEST_DATE
NO_OF_DAYS_IN_NEW
IN_PROGRESS_SINCE
CURRENT_STATUS
COMPLETED_CANCELLED_DATE
1234
1
2022-06-02 00:35:00
0
2022-06-02 00:47:00
Cancelled
2022-06-02 00:50:00
1234
2
2022-06-03 00:47:00
80.54319444444444444444444444444444444444
null
New
null
1231
5
2022-06-02 00:30:00
0
null
Draft
null
Note: there is not a next status for request_id 2 so it is assumed that the number of days in the New status is from the start of the new status until the current date.
db<>fiddle here