Выберите балансировку из базы данных с помощью codeigiter 3 и sql

Question

Я хотел бы получить остаток по кредиту клиента, когда он / она добавит или погасит ссуды Моя таблица:

-------------------------------------------------------------
loan_id | customer_id | placed_loan  | cleared_loan |  date |
-------------------------------------------------------------
    1    |     2       |    2,000.00 |              | 8/6/20|
------------------------------------------------------------
    2    |     4       |    1,000.00 |              | 9/6/20|
------------------------------------------------------------
    3    |     2       |             |    1,000.00  |10/6/20|
------------------------------------------------------------
    4    |     2       |   60,000.00 |              |12/6/20|
------------------------------------------------------------

Я бы хотел, чтобы результаты моего выбора были такими:

Customer id | Placed amount | Cleared amount | loan balance   | Date  |
-----------------------------------------------------------------------
       2     |   2,000.00    |                |  2,0000.00    | 8/6/20|
-----------------------------------------------------------------------
       2     |               |  1,000.000     |  1,0000.00    |10/6/20|
-----------------------------------------------------------------------
       2     |   60,000.00   |                |  61,000.00    |12/6/20|
-----------------------------------------------------------------------

Мои коды моделей:

$this->db->select('loan_id, CONCAT(SUM(placed_loan) - SUM(cleared_loan)) AS balance, CONCAT(t2_1.first_name, " ", t2_1.last_name) AS loan_added_by, CONCAT(t2_2.first_name, " ", t2_2.last_name) AS loan_cleared_by, CONCAT(t2_3.first_name, " ", t2_3.last_name) AS loan_updated_by, placed_loan, cleared_loan, loan_status, t2_4.customer_name, description, loan_added_on, loan_updated_on');
        $this->db->join('users t2_1', 't2_1.id = customers_loans.loan_added_by', 'left');
        $this->db->join('users t2_2', 't2_2.id = customers_loans.loan_cleared_by', 'left');
        $this->db->join('users t2_3', 't2_3.id = customers_loans.loan_updated_by', 'left');
        $this->db->join('customers t2_4', 't2_4.customer_id = customers_loans.customer_name', 'left');
        $this->db->join('customers_loans_info t2_5', 't2_5.loan_info_id = customers_loans.loan_info', 'left');
        $this->db->order_by('loan_id', 'desc');
        $this->db->where('customers_loans.customer_name ="'.$data['c_id'].'" AND loan_status <="2" AND loan_added_on >="'. $data['financial_year_start'].'" AND loan_added_on <="'. $data['financial_year_end'].'"');
        return $this->db->get('customers_loans')->result_array();

Как я могу получить столбец ссуды?

Answer 1

Используйте group_by() для суммирования остатка кредита.

$this->db->select('Customer_id , SUM(loan balance) AS AMOUNT');
$this->db->group_by('Customer_id');
$query = $this->db->get('TABLE_NAME');
$result = $query->result_array();