fixing my table using MySQL with null values - mysql

Question

I am using MySQL 8.0.
Here's my sample data:
https://www.db-fiddle.com/f/jYQJPV1X1XPbLp72LqA5CZ/1
Here's my code:
SELECT
COALESCE(t1.A, 0) AS CODE,
CASE WHEN t1.A IS NOT NULL THEN COALESCE(t2.DESCRIPTION, 'NOT VALID') ELSE 'TOTAL' END AS SEX,
t1.TOTAL,
ROUND(100.0 * t1.TOTAL / SUM(CASE WHEN t1.A IS NOT NULL THEN t1.TOTAL ELSE 0 END) OVER (), 2) AS PERCENT,
SUM(CASE WHEN t1.A IS NOT NULL THEN t1.TOTAL ELSE 0 END) OVER (ORDER BY t1.A) AS CUMULATIVE,
ROUND(100.0 * SUM(CASE WHEN t1.A IS NOT NULL THEN t1.TOTAL ELSE 0 END) OVER (ORDER BY t1.A) /
SUM(CASE WHEN t1.A IS NOT NULL THEN t1.TOTAL ELSE 0 END) OVER (), 2) AS CUMPERCENT
FROM
(
SELECT
A,
COUNT(*) AS TOTAL
FROM AA
GROUP BY A WITH ROLLUP
) t1
LEFT JOIN BB t2
ON t2.CODE = t1.A
ORDER BY
CODE;
Output:
CODE | SEX | TOTAL | PERCENT | CUMULATIVE | CUMPERCENT
0 TOTAL 1 16.67 0 0.00
0 TOTAL 7 116.67 0 0.00
1 Male 3 50.00 3 50.00
2 Female 2 33.33 5 83.33
3 NOT VALID 1 16.67 6 100.00
Expected Output:
CODE | SEX | TOTAL | PERCENT | CUMULATIVE | CUMPERCENT
0 TOTAL 7 100.00 0 0.00
1 Male 3 42.86 3 42.86
2 Female 2 28.57 5 71.43
3 NOT VALID 1 14.29 6 85.71
4 BLANK 1 14.29 7 100.00
I just want to make the table with NULL sex be included and rename it to 'BLANK'. Can you help me with this?

Answer 1

If you want a solution for this sample data, as you say in your comment, then this will work:
WITH cte AS (
SELECT MAX(CASE
WHEN a.A IS NULL THEN 4
WHEN b.code IS NULL THEN 3
ELSE a.A
END
) CODE,
CASE
WHEN a.A IS NULL THEN 'BLANK'
WHEN b.code IS NULL THEN 'NOT VALID'
ELSE b.description
END SEX,
COUNT(*) TOTAL,
ROUND(100.0 * COUNT(*) / SUM(COUNT(*)) OVER (), 2) PERCENT
FROM AA a LEFT JOIN BB b ON b.code = a.A
GROUP BY SEX
)
SELECT CODE, SEX, TOTAL, PERCENT,
SUM(TOTAL) OVER (ORDER BY CODE) CUMULATIVE,
ROUND(100.0 * SUM(TOTAL) OVER (ORDER BY CODE) / SUM(TOTAL) OVER (), 2) CUMPERCENT
FROM cte
UNION ALL
SELECT 0, 'TOTAL', COUNT(*), 100.00, 0, 0.00
FROM AA
ORDER BY CODE
See the demo.
Results:
> CODE | SEX | TOTAL | PERCENT | CUMULATIVE | CUMPERCENT
> ---: | :-------- | ----: | ------: | ---------: | ---------:
> 0 | TOTAL | 7 | 100.00 | 0 | 0.00
> 1 | Male | 3 | 42.86 | 3 | 42.86
> 2 | Female | 2 | 28.57 | 5 | 71.43
> 3 | NOT VALID | 1 | 14.29 | 6 | 85.71
> 4 | BLANK | 1 | 14.29 | 7 | 100.00

Answer 2

WITH
cte1 AS ( SELECT AA.A AS code,
CASE WHEN AA.A IS NULL
THEN 'BLANK'
WHEN BB.description IS NULL
THEN 'NOT VALID'
ELSE BB.description
END description,
COUNT(*) AS amount
FROM AA
LEFT JOIN BB ON AA.A = BB.code
GROUP BY AA.A, BB.description ),
cte2 AS ( SELECT SUM(amount) amount, MAX(code) + 1 code
FROM cte1 )
SELECT 0 code,
'TOTAL' description,
amount,
100 percent,
0 cumulative,
0 cumulative_percent
FROM cte2
UNION ALL
SELECT COALESCE(cte1.code, cte2.code) code,
cte1.description,
cte1.amount,
100 * cte1.amount / cte2.amount,
SUM(cte1.amount) OVER (ORDER BY COALESCE(cte1.code, cte2.code)),
100 * SUM(cte1.amount) OVER (ORDER BY COALESCE(cte1.code, cte2.code)) / cte2.amount
FROM cte1
CROSS JOIN cte2
fiddle