nesting multiple queries in SQL - sql

Question

I want to know in the year in which more goals were scored (in total), how many goals were scored by and against team 1 when team 1 is either a or b.
My table looks like this:
year
team1
team2
score_team1
score_team2
1
a
x
10
5
1
b
y
4
3
2
a
z
2
7
2
a
x
9
6
2
b
z
0
7
This is the output that I need:
year
team
max_score_team1
max_score_team2
2
a
11
13
2
b
0
7
I know that more goals were scored in year 2 by doing this query:
select year, sum(score_team1 + score_team2) as total
from data
group by year
order by sum(score_team1 + score_team2) desc
limit(1)
Now I want to know how many goals were scored by and against team1 when team1 is either a or b. I know how to write the queries separately but how can I nest them in one query so I can get the results in one table like the one above?

Answer 1

To obtain the results you desire in a single table, you can use a SQL query with a GROUP BY clause and a HAVING clause to filter for the year in which the most goals were scored. If you are using MySQL, the query might look something like this:
SELECT year, team1,
SUM(score_team1) AS max_score_team1,
SUM(score_team2) AS max_score_team2
FROM data
GROUP BY year, team1
HAVING year = (SELECT year
FROM data
GROUP BY year
ORDER BY SUM(score_team1 + score_team2) DESC
LIMIT 1)
AND team1 IN ('a', 'b')
The GROUP BY clause groups the results by year and team, and the HAVING clause is used to filter only the results for the year in which the most goals were scored and for team 'a' or 'b'. The nested query in the HAVING clause is used to obtain the year in which the most goals were scored.
The result of the query would be something like this:
year
team1
max_score_team1
max_score_team2
2
a
11
13
2
b
0
7

Answer 2

Use conditional aggregation to count team #1's goals.
select
year,
sum(score_team1 + score_team2) as total,
sum(case when team1 = 1 then score_team1 else 0 end) +
sum(case when team2 = 1 then score_team2 else 0 end) as scored_by_team_1,
sum(case when team1 = 1 then score_team2 else 0 end) +
sum(case when team2 = 1 then score_team1 else 0 end) as scored_against_team_1
from data
group by year
order by total desc
limit 1;
The problem with that: If there is more than one year with the top goals count, you'd pick one arbitrarily.
So, instead:
select year, total, scored_by_team_1, scored_against_team_1
from
(
select
year,
sum(score_team1 + score_team2) as total,
max(sum(score_team1 + score_team2)) over () as max_total,
sum(case when team1 = 1 then score_team1 else 0 end) +
sum(case when team2 = 1 then score_team2 else 0 end) as scored_by_team_1,
sum(case when team1 = 1 then score_team2 else 0 end) +
sum(case when team2 = 1 then score_team1 else 0 end) as scored_against_team_1
from data
group by year
) with_max_total
where total = max_total;