Você pode usar várias expressões de tabela comuns, computando cada uma separadamente e juntando - apenas para entender o que está acontecendo.
SQL Fiddle
Consulta :
WITH aud(manager_email,Total_audits) AS
(SELECT manager_email,
SUM (
CASE
WHEN audit_eligible = 'Y'
THEN audits_required
END )
FROM REQUIRED_AUDITS
GROUP BY manager_email
), --Total_audits
scores(manager_email,Audits_Performed) AS
(SELECT manager_email,
COUNT ( ID )
FROM SCORE_ENTRY s
GROUP BY manager_email
) --Audits_Performed
SELECT h.manager_email manager,
a.Total_audits,
s.Audits_Performed,
100 * s.Audits_Performed / a.Total_audits percentage_complete
FROM HR h
LEFT OUTER JOIN aud a
ON h.manager_email = a.manager_email
LEFT OUTER JOIN scores s
ON h.manager_email = s.manager_email
ORDER BY 2 DESC NULLS LAST
Resultados :
| MANAGER | TOTAL_AUDITS | AUDITS_PERFORMED | PERCENTAGE_COMPLETE |
|---------------|--------------|------------------|---------------------|
| [email protected] | 10 | 1 | 10 |
| [email protected] | 9 | 2 | 22.22222222222222 |
| [email protected] | (null) | (null) | (null) |
| [email protected] | (null) | (null) | (null) |
| [email protected] | (null) | (null) | (null) |
