How to get data of joined table using query() method - mysql

Question

I have an issue with getting data of the joined table if I use query().
I did not get the data of product table, how can I solve this using query() without using Active record?
Here is my db table structure
category table
+--------------------------+
| cId | added | category |
+-----+--------+-----------+
| 1 | 1.2.20 | PC |
| 2 | 1.7.20 | electron |
+-----+--------+-----------+
product table
+--------------------------+
| id | cId | cost |
+-----+--------+-----------+
| 1 | 1 | 3000 |
| 1 | 2 | 9000 |
+-----+--------+-----------+
My Model
protected $table = 'category';
public function showProduct()
{
$sql = "SELECT
category.*, COALESCE(SUM(product.cost),0) as price
FROM category
JOIN product
ON product.cId = category.cId
GROUP BY category.cId
";
$this->db->query($sql);
return $this;
}
My Controller
public function index()
{
$result = $this->model->showProduct();
echo "<pre>";
print_r($result->asObject()->paginate(1));
//pagination
$pager = $this->model->showProduct()->pager->links();
}
Result I get
Array
(
[0] => stdClass Object
(
[cId] => 1
[added] => 1.2.20
[category] => PC
)
[1] => stdClass Object
(
[cId] => 2
[added] => 1.7.20
[category] => electron
),
)

Answer 1

You are requested to run this code.
SELECT category.cId,category.added,category.category,product.id,COALESCE(SUM(product.cost),0) as price
FROM category,product
WHERE category.cId=product.cId
GROUP BY category.cId;
If you are using CodeIgniter-4 then you can easily write this using Query Builder Class.

Answer 2

$sql="SELECT category*,product* FROM category INNER JOIN product.cid=category.id WHERE category.id";

Answer 3

I found solution to this by setting this table property within a function.
Model
$protected $table = array("default bd table here");
public function showProduct()
{
$this->table = array('category');
$sql = "SELECT
category.*, COALESCE(SUM(product.cost),0) as price
FROM category
JOIN product
ON product.cId = category.cId
GROUP BY category.cId
";
$this->db->query($sql);
return $this;
}
My Controller
public function index()
{
$result = $this->model->showProduct();
//pagination
$pager = $this->model->showProduct()->pager->links();
}