%Total from SQL Table - sql

Question

Using below code;
SELECT CASE GROUPING_ID(period) WHEN 1 THEN 'TOTAL' ELSE TO_CHAR(period) END AS period,
COUNT(CASE status WHEN 'Completed' THEN 1 END) AS completed,
COUNT(CASE status WHEN 'WIP' THEN 1 END) AS wip,
COUNT(CASE status WHEN 'Not Started' THEN 1 END) AS not_started,
COUNT(*) AS Total
FROM transition_tasks_new
GROUP BY ROLLUP(period)
ORDER BY period;
I'm getting data in the attached format:
which is fine. However, I need to get the %complete for each of them.
For ex - % Pre-Update "Complete" would be 2/28 i.e 7%;
I wrote this query;
SELECT SUM(CASE WHEN period = '1-Pre Update' THEN 1 ELSE 0 END) AS value,
COUNT(taskid) AS max_value
FROM transition_tasks_new
WHERE status='Completed'
but it's not working as intended.

Answer 1

Divide the value by the total and multiply by 100 to calculate the percentage:
SELECT CASE GROUPING_ID(period) WHEN 1 THEN 'TOTAL' ELSE TO_CHAR(period) END
AS period,
COUNT(CASE status WHEN 'Completed' THEN 1 END) AS completed,
ROUND(COUNT(CASE status WHEN 'Completed' THEN 1 END)/COUNT(*) * 100, 3)
AS percent_completed,
COUNT(CASE status WHEN 'WIP' THEN 1 END) AS wip,
COUNT(CASE status WHEN 'Not Started' THEN 1 END) AS not_started,
COUNT(*) AS total
FROM tasks
GROUP BY ROLLUP(period)
ORDER BY period;
Which, for the sample data:
CREATE TABLE tasks (period, status) AS
SELECT 1, 'Completed' FROM DUAL CONNECT BY LEVEL <= 3 UNION ALL
SELECT 1, 'WIP' FROM DUAL CONNECT BY LEVEL <= 2 UNION ALL
SELECT 1, 'Not Started' FROM DUAL CONNECT BY LEVEL <= 1 UNION ALL
SELECT 1, 'Other' FROM DUAL CONNECT BY LEVEL <= 1 UNION ALL
SELECT 2, 'Completed' FROM DUAL CONNECT BY LEVEL <= 2 UNION ALL
SELECT 2, 'WIP' FROM DUAL CONNECT BY LEVEL <= 1 UNION ALL
SELECT 3, 'Completed' FROM DUAL CONNECT BY LEVEL <= 4 UNION ALL
SELECT 3, 'Not Started' FROM DUAL CONNECT BY LEVEL <= 2;
Outputs:
PERIOD
COMPLETED
PERCENT_COMPLETED
WIP
NOT_STARTED
TOTAL
1
3
42.857
2
1
7
2
2
66.667
1
0
3
3
4
66.667
0
2
6
TOTAL
9
56.25
3
3
16
db<>fiddle here

Answer 2

SELECT X.*,
ROUND(X.COMPLETED / X.TOTAL * 100,
2) AS PERCENT_COMPLETE
FROM
(WITH SAMPLE_DATA AS
(SELECT '1-Pre-Update' AS PERIOD,
3 AS WIP,
2 AS COMPLETED,
23 AS NOT_STARTED) SELECT PERIOD,
SUM(WIP) AS WIP,
SUM(COMPLETED) AS COMPLETED,
SUM(NOT_STARTED) AS NOT_STARTED,
SUM(WIP + COMPLETED + NOT_STARTED) AS TOTAL
FROM SAMPLE_DATA
GROUP BY PERIOD) X