Bank Account Summary Problem

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+--------------+---------+
| Column Name  | Type    |
+--------------+---------+
| user_id      | int     |
| user_name    | varchar |
| credit       | int     |
+--------------+---------+
user_id is the primary key for this table.
Each row of this table contains the current credit information for each user.

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+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| trans_id      | int     |
| paid_by       | int     |
| paid_to       | int     |
| amount        | int     |
| transacted_on | date    |
+---------------+---------+
trans_id is the primary key for this table.
Each row of this table contains the information about the transaction in the bank.
User with id (paid_by) transfer money to user with id (paid_to).

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Users table:
+------------+--------------+-------------+
| user_id    | user_name    | credit      |
+------------+--------------+-------------+
| 1          | Moustafa     | 100         |
| 2          | Jonathan     | 200         |
| 3          | Winston      | 10000       |
| 4          | Luis         | 800         | 
+------------+--------------+-------------+

Transactions table:
+------------+------------+------------+----------+---------------+
| trans_id   | paid_by    | paid_to    | amount   | transacted_on |
+------------+------------+------------+----------+---------------+
| 1          | 1          | 3          | 400      | 2020-08-01    |
| 2          | 3          | 2          | 500      | 2020-08-02    |
| 3          | 2          | 1          | 200      | 2020-08-03    |
+------------+------------+------------+----------+---------------+

Result table:
+------------+------------+------------+-----------------------+
| user_id    | user_name  | credit     | credit_limit_breached |
+------------+------------+------------+-----------------------+
| 1          | Moustafa   | -100       | Yes                   | 
| 2          | Jonathan   | 500        | No                    |
| 3          | Winston    | 9900       | No                    |
| 4          | Luis       | 800        | No                    |
+------------+------------+------------+-----------------------+
Moustafa paid $400 on "2020-08-01" and received $200 on "2020-08-03", credit (100 -400 +200) = -$100
Jonathan received $500 on "2020-08-02" and paid $200 on "2020-08-08", credit (200 +500 -200) = $500
Winston received $400 on "2020-08-01" and paid $500 on "2020-08-03", credit (10000 +400 -500) = $9990
Luis didn't received any transfer, credit = $800

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select *, (case when credit < 0 then "Yes" else "No" end) as credit_limit_breached
from (select u.user_id, u.user_name, 
      credit + ifnull(sum((case when u.user_id=t.paid_by then -t.amount
                               else t.amount end)), 0) as credit
      from Users u
      left join Transactions t
      on u.user_id = t.paid_by or u.user_id = t.paid_to
      group by u.user_id, u.user_name) t