导出到CSV时操纵数据？

Question

I'm using CodeIgniter v2.2.4

Consider the following code to export/download a CSV file representing results from a database query.

CONTROLLER:

public function export_csv($id = NULL)
{   
    $this->load->dbutil();
    $this->load->helper('download');

    $query = $this->my_model->create_csv($id);  // call the model

    $data = $this->dbutil->csv_from_result($query, ',');

    force_download( $id . '.csv', $data );
}

MODEL:

public function create_csv($id)
{
    $this->db->from('mytable');

    $this->db->where('id', $id);

    $this->db->select('
        id            AS `ID`,
        full_name     AS `Full Name`,
        company_name  AS `Company Name`,
        phone         AS `Phone Number`,
        select_list   AS `User Options`
    ', FALSE);

    return $this->db->get();
}

The code above is working, however the select_list value is 0, 1, or 2 and that's inserted into the CSV export. How can I manipulate these values into more meaningful text for my final CSV file?

Example:

'DB value' => 'insert into CSV'
         0 => 'N/A',
         1 => 'foo',
         2 => 'bar'

Answer 1

Easiest way is to use a select statement along these lines

$this->db->select(
   "id            AS `ID`,
    full_name     AS `Full Name`,
    company_name  AS `Company Name`,
    phone         AS `Phone Number`,
    CASE select_list WHEN = 1 THEN 'foo' WHEN = 2 THEN 'bar' ELSE 'N/A' END
    AS `User Options`", FALSE);

CANCEL THAT! It is wrong.

It should be as follows when using the optional expression after CASE, i.e. CASE select_list ...

$this->db->select(
   "id            AS `ID`,
    full_name     AS `Full Name`,
    company_name  AS `Company Name`,
    phone         AS `Phone Number`,
    CASE select_list WHEN 1 THEN 'foo' WHEN 2 THEN 'bar' ELSE 'N/A' END
    AS `User Options`", FALSE);

I was mixing the different forms the statement can use in the first (incorrect) example.