Done sql4 problems

Problem 1.sql

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+# Write your MySQL query statement below
+with cte as(
+select  employee_id,experience,salary, sum(salary) over(partition by experience order by salary) as Acccandidates
+from Candidates
+)
+
+select 'Senior' as experience,count(employee_id) as accepted_candidates
+from cte
+where experience='Senior' and Acccandidates<=70000
+union
+select 'Junior' as experience,count(employee_id) as accepted_candidates
+from cte
+where experience='Junior' and Acccandidates<= (select 70000-ifnull(max(Acccandidates),0) from cte where experience='Senior' and Acccandidates<=70000);

Problem 2.sql

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+# Write your MySQL query statement below
+with cte as(
+select home_team_id as hid, away_team_id as aid, home_team_goals as htg, away_team_goals as atg
+from matches
+union all
+select away_team_id as hid, home_team_id as aid, away_team_goals as htg, home_team_goals as atg
+from matches)
+
+
+select teams.team_name,count(hid) as matches_played,
+sum(case when htg > atg then '3'
+        when htg = atg then '1'
+        else 0
+        end) points,sum(htg) as goal_for,sum(atg) as goal_against ,(sum(htg)-sum(atg)) as goal_diff
+from cte
+join teams on cte.hid=teams.team_id
+group by hid
+order by points desc,goal_diff desc,team_name;
+

Problem 3.sql

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+-- # Write your MySQL query statement below
+select s.name
+from SalesPerson s 
+where s.sales_id not in (
+    select o.sales_id
+    from orders o
+    join company c on o.com_id=c.com_id
+    where name='Red'
+)

Problem 4.sql

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+with cte as(
+select requester_id as id from RequestAccepted
+union all
+select accepter_id as id  from RequestAccepted),
+
+counts as(
+    select id,count(*) as num
+    from cte
+    group by id
+)
+
+select id,num from counts
+where num=(select max(num) from counts);
+