machadolivia

SELECT
  dep.nome AS departamento,
  COUNT(DISTINCT emp.matr) AS qtd_empregados,
  ROUND(AVG(COALESCE(venc.valor, 0)), 2) AS media_salarial,
  ROUND(MAX(COALESCE(venc.valor, 0)), 2) AS maior_salario,
  ROUND(MIN(COALESCE(venc.valor, 0)), 2) AS menor_salario
FROM
  departamento dep
LEFT JOIN
  empregado emp ON dep.cod_dep = emp.gerencia_cod_dep

machadolivia

--Questão 1: Letra a 

SELECT 
	sc.name as school_name,
	st.enrolled_at, 
	COUNT(*) as students_count,
	SUM(c.price) as Total_value
FROM students st
JOIN courses C on st.course_id = c.id
join schools sc on c.school_id = sc.id