Get Row Totals for Dynamically Created Pivoted Table - sql

Question

In PostgreSQL I have a table like this:
CREATE TABLE cross_table (brand varchar(10), gender varchar(10), sales int);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Nike', 'Male', 10);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Nike', 'Male', 20);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Adidas', 'Woman', 20);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Nike', 'Male', 10);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Adidas', 'Woman', 30);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Puma', 'Woman', 40);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Puma', 'Male', 10);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Nike', 'Male', 20);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Puma', 'Woman', 10);
INSERT INTO cross_table (brand, gender, sales) VALUES ('Adidas', 'Woman', 20);
And then I run this query to get brand as rows, gender as columns ans sales as value:
with main_query as (
SELECT brand,
GROUPING(brand) AS "brand_grouping",
gender,
GROUPING(gender) AS "gender_grouping",
sum(sales) AS "sales"
FROM cross_table
GROUP BY ROLLUP (brand, gender)
),
second_query AS (
SELECT brand,
brand_grouping,
cast(
json_object_agg(
gender,
sales
ORDER BY gender DESC
) FILTER (WHERE gender_grouping = 0) AS jsonb) "gender",
SUM(sales) AS "sales"
FROM main_query
GROUP BY (brand, brand_grouping)
)
SELECT brand,
gender,
sales
FROM second_query
ORDER BY brand_grouping, brand
This would produce the following result:
brand
gender
sales
adidas
{ "Woman": 70 }
140
nike
"Male": 60
120
puma
"Male": 10, "Woman": 50
120
NULL
NULL
190
Please note: gender column is now in object but brackets won't show in the table view here on Stackoverflow.
This is fine, only problem is that it is missing row totals for the pivoted "gender" column. I can solve this hardcoded by changing last query to this:
SELECT brand,
CASE WHEN gender IS null THEN
jsonb_build_object(
'Woman', SUM(("gender"->>'Woman')::float8) OVER (),
'Male', SUM(("gender"->>'Male')::float8) OVER ()
) ELSE "gender" END AS "gender",
sales
FROM second_query
ORDER BY brand_grouping, brand
Getting this result:
brand
gender
sales
adidas
{"Woman": 70}
140
nike
"Male": 60
120
puma
"Male": 10, "Woman": 50
120
NULL
"Male": 70, "Woman": 120
190
Which is correct but I need to do this dynamically without knowing the keys (Male/Woman) of "gender".
Does anyone know how to do this?

Answer 1

Try this :
SELECT brand
, jsonb_object_agg(gender, sales) AS gender
, sum(sales) AS sales
FROM (
SELECT brand
, gender
, sum(sales) AS sales
FROM cross_table
GROUP BY ROLLUP(brand), gender
) AS a
GROUP BY brand
Result :
brand
gender
sales
null
{"Male": 70, "Woman": 120}
190
Adidas
{"Woman": 70}
70
Nike
{"Male": 60}
60
Puma
{"Male": 10, "Woman": 50}
60
see dbfiddle