高频SQL50题（基础版）_1193.每月交易I

高频 SQL 50 题（基础版）_1193. 每月交易 I

# Write your MySQL query statement below select substr(trans_date,1,7) as month, country, count(*) as trans_count, count(case when state='approved' THEN 1 END) as approved_count , sum(amount) as trans_total_amount , coalesce(sum(case when state='approved' THEN amount END),0) as approved_total_amount from Transactions group by month,country