一个简单的银行账户的衍生账户余额vs存储账户余额?

So, its like our normal bank accounts where we have a lot of transactions which result in inflow or outflow of money. The account balance can always be derived by simply summing up the transaction values. What would be better in this case, storing the updated account balance in the database or re-calculating it whenever needed?So, its like our normal bank accounts where we