DROP TABLE IF EXISTS my_table;
CREATE TABLE my_table
(transaction_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,client_id INT NOT NULL
,action_type VARCHAR(12) NOT NULL
,action_amount INT NOT NULL
);
INSERT INTO my_table(client_id,action_type,action_amount) VALUES
(1 ,'debit', 1000),
(1 ,'credit', 100),
(1 ,'credit', 500),
(2 ,'debit', 1000),
(2 ,'credit', 1200),
(3 ,'debit', 1000),
(3 ,'credit', 1000),
(4 ,'debit', 1000);
SELECT client_id
, SUM(COALESCE(CASE WHEN action_type = 'debit' THEN action_amount END,0)) total_debits
, SUM(COALESCE(CASE WHEN action_type = 'credit' THEN action_amount END,0)) total_credits
, SUM(COALESCE(CASE WHEN action_type = 'debit' THEN action_amount END,0))
- SUM(COALESCE(CASE WHEN action_type = 'credit' THEN action_amount END,0)) balance
FROM my_table
GROUP
BY client_id
HAVING balance <> 0;
+-----------+--------------+---------------+---------+
| client_id | total_debits | total_credits | balance |
+-----------+--------------+---------------+---------+
| 1 | 1000 | 600 | 400 |
| 2 | 1000 | 1200 | -200 |
| 4 | 1000 | 0 | 1000 |
+-----------+--------------+---------------+---------+
