Question

I have two tables. Table “user” contains user_id, user_name. Table “Transactions” contains user_id, transactions

Eg:
TABLE USER:

+---------+-----------+
| user_id | user_name |
+---------+-----------+
| 1       | Ram       |
| 2       | John      |
+---------+-----------+

TABLE Transactions

+---------+---------+--------------+
| user_id | type    | transactions |
+---------+---------+--------------+
| 1       | credit  | 500          |
| 1       | debit   | 300          |
| 2       | credit  | 250          |
| 1       | credit  | 450          |
| 2       | credit  | 100          |
| 1       | debit   | 250          |
| 2       | debit   | 50           |
+---------+---------+--------------+

I want to display the result by adding all credit amount and deduct all debit amount as shown below:

+-----------+--------------+-------------+-------------+
| user_name | Total Credit | Total debit | Grand Total |
+-----------+--------------+-------------+-------------+
| Ram       | 950          | 550         | 400         |
| John      | 350          | 50          | 300         |
+-----------+--------------+-------------+-------------+

How can I do this?

Answer 1

Here’s the query:

SELECT
    u.user_name, 
    SUM(IF(t.type = 'credit', t.transactions, 0)) AS totalcredit,
    SUM(IF(t.type = 'debit', t.transactions, 0)) AS totaldebit,
    SUM(IF(t.type = 'credit', -1, 1) * t.transactions) AS total
FROM
    transactions t
INNER JOIN
    users u
ON
    u.user_id = t.user_id
GROUP BY
    u.user_name