The match is OVER
The OVER() clause allows you to apply an aggregate function across a dataset, similar to subqueries in SELECT. The OVER() clause offers significant benefits over subqueries in SELECT -- namely, your queries will run faster, and the OVER() clause has a wide range of additional functions and clauses you can include with it which we will cover later in this chapter.
In this exercise, you will revise some queries from previous chapters using the OVER() clause.
Questo esercizio fa parte del corso
Data Manipulation in SQL
Istruzioni dell'esercizio
- Select the match
ID, countryname,season,home_goal, andaway_goalfrom thematchandcountrytables. - Complete the query that calculates the average number of goals scored overall and then includes the aggregate value in each row using a window function.
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
SELECT
-- Select the match id, country name, season, home, and away goals
___,
c.___ AS country,
m.season,
___.home_goal,
___,
-- Use a window to include the aggregate average in each row
___(___.home_goal + ___) ___ AS overall_avg
FROM match AS m
LEFT JOIN country AS c ON m.country_id = c.id;