%% sql
SELECT
COUNT(DISTINCT c.email) CountRockListeners
FROM
customer c
JOIN invoice i ON c.customer_id = i.customer_id
JOIN invoice_line il ON i.invoice_id = il.invoice_id
JOIN track t ON il.track_id = t.track_id
JOIN genre g ON t.genre_Id = g.genre_Id
WHERE g.name = 'Rock' OR g.name = 'Pop'
我有这个SQL代码,想返回Rock和Pop侦听器的计数,但它只返回Rock的计数59,Pop是32。 所以我希望它返回59 + 32 请指教吗?
答案 0 :(得分:1)
也许您想要条件聚合:
Foo