MySql中的查詢語法錯誤

Question

這是我的查詢，它給MySql中的SQL手動語法錯誤。

select 
count(case when v.created_at = vv.minva then user_id) as num_new_users 
from bills v 
join (select user_id, min(created_at) as minva from bills t group by user_id) vv 
on v.user_id = vv.user_id 

有人可以幫我解決這個問題嗎？

Answer 1

的case statement應end

select 
count(case when v.created_at = vv.minva then user_id end) as num_new_users 
from bills v 
join (select user_id, min(created_at) as minva from bills t group by user_id) vv 
on v.user_id = vv.user_id 

Answer 2

結束你忘了CASE語句中使用end。

select 
count(case when v.created_at = vv.minva then user_id end) as num_new_users 
from bills v 
join (select user_id, min(created_at) as minva from bills t group by user_id) vv 
on v.user_id = vv.user_id