Find 10 users with the highest sum of product sales - database

Question

I have two classes, User and Sell. I am trying to compose a request to find 10 people with the largest sum of sales
Task:
Find 10 users
with the highest sum of product sales
find the largest count of sales
select sum_amount_total.*
from (select sum(amount) as total_amount
from
User as u
join Sell as a on u.id = a.seller
group by amount
) as amountSum
join (select sum(amount) as sum_amount
from
Sell
group by
seller
order by
sum_amount desc
) as sum_amount_total on amountSum.total_amount > sum_amount_total.sum_amount limit 2;
create table script
Create table User (id int, name varchar(255));
Truncate table User;
insert into User (id, name) values ('1', 'Joe');
insert into User (id, name) values ('2', 'Henry');
Create table Sell (id int, seller INT, buyer INT, amount FLOAT);
Truncate table Sell;
insert into Sell (id, seller, buyer, amount) values (1, 1, 2, 134444.7);
insert into Sell (id, seller, buyer, amount) values (2, 2, 1, 1241.7);
insert into Sell (id, seller, buyer, amount) values (3, 1, 2, 123.4);
insert into Sell (id, seller, buyer, amount) values (4, 1, 2, 1000000.0);
Problem:
how to simplify the sql script?
I do not understand why my request is not working correctly. Example:
select * from Sell;
Result:
id|seller|buyer|amount
1, 1, 2, 134445
2, 1, 3, 1241.7
3, 2, 1, 123.4
4, 3, 3, 123.4
5, 3, 2, 134445
6, 2, 3, 1241.7
7, 2, 1, 123.4
8, 1, 3, 123.4
9, 1, 3, 10000
10,1, 3, 1000000
my query(1) for finding the largest amount:
sum_amount
134568.10312652588
134568.10312652588
1488.4999542236328
1488.4999542236328
1488.4999542236328
1488.4999542236328
My request does not correctly calculate the largest sum
What needs to be changed for the sql script to work and add a condition to search for the largest count of sales?
Thanks in advance for your answer!

Answer 1

Simplifying your sql script for table User :
insert into User (id, name) values ('1', 'Joe'), ('2', 'Henry');
instead of
insert into User (id, name) values ('1', 'Joe');
insert into User (id, name) values ('2', 'Henry');
The same for table Sell :
insert into Sell (id, seller, buyer, amount) values (1, 1, 2, 134444.7), (2, 2, 1, 1241.7), (3, 1, 2, 123.4), (4, 1, 2, 1000000.0);
Then finding 10 users with the highest sum of product sales :
WITH list AS
(
select seller, sum(amount) as total_amount
from Sell
group by seller
order by total_amount DESC
limit 10
)
select u.*, l.total_amount
from list AS l
inner join user AS u
on u.id = l.seller
Finally finding 10 users with the largest count of product sales :
WITH list AS
(
select seller, coun(*) as total_count
from Sell
group by seller
order by total_count DESC
limit 10
)
select u.*, l.total_count
from list AS l
inner join user AS u
on u.id = l.seller

Answer 2

create table script
Create table User(id int, name varchar(255));
Truncate table Users;
insert into Users (id, name) values ('1', 'Joe');
insert into Users (id, name) values ('2', 'Henry');
insert into Users (id, name) values ('3', 'Liza');
Create table Sell (id int, seller INT, buyer INT, amount FLOAT);
Truncate table Sell;
insert into Sell (id, seller, buyer, amount) values (1, 1, 2, 134444.7);
insert into Sell (id, seller, buyer, amount) values (2, 2, 1, 1241.7);
insert into Sell (id, seller, buyer, amount) values (3, 1, 2, 123.4);
insert into Sell (id, seller, buyer, amount) values (4, 1, 2, 1000000.0);
insert into Sell (id, seller, buyer, amount) values (5, 3, 2, 134445);
insert into Sell (id, seller, buyer, amount) values (6, 2, 3, 1241.7);
insert into Sell (id, seller, buyer, amount) values (7, 2, 1, 123.4);
insert into Sell (id, seller, buyer, amount) values (8, 3, 3, 123.4);
insert into Sell (id, seller, buyer, amount) values (9, 1, 3, 10000);
insert into Sell (id, seller, buyer, amount) values (10,1, 3, 1000000);
query to get count of sales
SELECT name,count(Sell.id) as nsales,sum(amount),rank()
over(order by count(Sell.id) desc)
from Sell
inner join Users
on(seller=Users.id) group by name
limit 10;
name | nsales | sum | rank
-------+--------+-----------+------
Joe | 5 | 2144568.1 | 1
Henry | 3 | 2606.8 | 2
Liza | 2 | 134568.4 | 3
and query to get top of amount
SELECT name,count(Sell.id) as nsales,sum(amount),rank()
over(order by sum(amount) desc)
from Sell
inner join Users
on(seller=Users.id) group by name
limit 10;
name | nsales | sum | rank
-------+--------+-----------+------
Joe | 5 | 2144568.1 | 1
Liza | 2 | 134568.4 | 2
Henry | 3 | 2606.8 | 3
same result without ranking
SELECT name,count(Sell.id) as nsales,sum(amount) amount_sum
from Sell inner join Users on(seller=Users.id)
group by name
order by amount_sum desc
limit 10;
name | nsales | amount_sum
-------+--------+------------
Joe | 5 | 2144568.1
Liza | 2 | 134568.4
Henry | 3 | 2606.8
SELECT name,count(Sell.id) as nsales,sum(amount) amount_sum
from Sell inner join Users on(seller=Users.id)
group by name
order by nsales desc
limit 10;
name | nsales | amount_sum
-------+--------+------------
Joe | 5 | 2144568.1
Henry | 3 | 2606.8
Liza | 2 | 134568.4