基于多个案例的Mysql获取记录

Question

我有merchant_credit_history表，我存储商家信用卡，借记卡和交易类型。

我希望根据交易类型对CREDIT或DEBIT进行汇总。

记录

我试过这个：

SELECT SUM（ABS（借记））为 dealer_credit 来自merchant_credits_history WHERE transaction_type ='premium_debit'和merchant_id ='x'

UNION

SELECT SUM（ABS（credit））为 dealer_margin_earned 来自merchant_credits_history WHERE transaction_type ='margin_credit'和merchant_id ='x'

并将其视为

如果我能有更好的查询以及单独的键值对中的值

，我将不胜感激

Answer 1

return

因此，您可以获得每个merchant_id的一对信用卡，借方值。

Answer 2

SELECT SUM(Debit), SUM(CREDIT) FROM 
   (SELECT 
      CASE WHEN transaction_type='premium_debit' THEN debit ELSE 0 END as Debit, 
      CASE WHEN transaction_type='margin_credit' THEN credit ELSE 0 END as Credit
   FROM Customers WHERE merchant_id='x')

Answer 3

试试这个：

SELECT SUM(ABS(credit)) as Credit, SUM(ABS(debit)) AS Debit, 
transaction_type FROM merchant_credits_history merchant_id='x'
GROUP BY (transaction_type);