CodeIgniter Active Record multiple

Question

我在CodeIgniter中有以下MY-SQL查询，我正在尝试 [sub_product_price] * [数量] 的乘法并将其显示为乘以。任何人都可以帮助我。我查看了CodeIgniter用户指南，但找不到与此相关的任何内容。

感谢!!!!

 function product_profit_chart(){

    $this->db->select(array(
        'tbl_sub_products.sub_product_name',
        'tbl_sub_products.sub_product_id',
        'tbl_sub_products.sub_product_price',
        'SUM(tbl_order_products.quantity) as quantity'
    ));
    $this->db->from('tbl_order_products');
    $this->db->join('tbl_order_product_details', 'tbl_order_product_details.order_id=tbl_order_products.order_id','LEFT');
    $this->db->join('tbl_sub_products', 'tbl_sub_products.sub_product_id=tbl_order_products.product_id','LEFT');
    $this->db->group_by('tbl_sub_products.sub_product_id');
    $this->db->where('tbl_order_product_details.order_status', 'completed');
    $query = $this->db->get();
    return $query->result();

}

返回上述查询的数组。

[1] => stdClass Object
        (
            [sub_product_name] => chocolate cake 500G
            [sub_product_id] => SP001
            [sub_product_price] => 1000.00
            [quantity] => 14
        )

[2] => stdClass Object
        (
            [sub_product_name] => Sausage Bun
            [sub_product_id] => SP002
            [sub_product_price] => 50.00
            [quantity] => 16
        )

Answer 1

按如下方式更改您的功能：

function product_profit_chart（）{

$this->db->select(array(
    'tbl_sub_products.sub_product_name',
    'tbl_sub_products.sub_product_id',
    'tbl_sub_products.sub_product_price',
    'SUM(tbl_order_products.quantity) as quantity',
    'SUM(tbl_sub_products.sub_product_price * quantity) as amount'
));
$this->db->from('tbl_order_products');
$this->db->join('tbl_order_product_details', 'tbl_order_product_details.order_id=tbl_order_products.order_id','LEFT');
$this->db->join('tbl_sub_products', 'tbl_sub_products.sub_product_id=tbl_order_products.product_id','LEFT');
$this->db->group_by('tbl_sub_products.sub_product_id');
$this->db->where('tbl_order_product_details.order_status', 'completed');
$query = $this->db->get();
return $query->result();

}

希望这会对你有所帮助。

Answer 2

只需在执行乘法的位置再添加一个选择项：

$this->db->select(array(
    'tbl_sub_products.sub_product_name',
    'tbl_sub_products.sub_product_id',
    'tbl_sub_products.sub_product_price',
    'SUM(tbl_order_products.quantity) as quantity',
    /* add this column: */
    'SUM(tbl_order_products.quantity) * tbl_sub_products.sub_product_price as total'
));

See this demo （不是Codeigniter Active Record，但显示工作查询逻辑）

Answer 3

未经测试，它使用别名进行查询并使用select_sum()而不是在select查询中编写它

function product_profit_chart(){
    $this->db->select('sub_product_name', 'sub_product_id', 'sub_product_price');
    $this->db->select_sum('sub_prod.sub_product_price * prod.quantity as quantity');
    $this->db->from('tbl_order_products prod');
    $this->db->join('tbl_order_product_details prod_details', 'prod_details.order_id=prod.order_id','LEFT');
    $this->db->join('tbl_sub_products as sub_prod', 'sub_prod.sub_product_id=prod.product_id','LEFT');
    $this->db->group_by('sub_prod.sub_product_id');
    $this->db->where('prod_details.order_status', 'completed');
    $query = $this->db->get();
    return $query->result();
}