更好的查询解决方案

Question

$query = $this->db->query("SELECT field_name FROM table_name;");

        $getData= array();

        foreach ($query->result() as $row) {

            array_push($getData, $row->field_name);
        }

I use codeigniter, for every table that I need to manage if the data exist for update or make a new insert I use this code so i would like to see is there are more options for dont replicate the code every time. I'm just a student, sorry for mi english

Answer 1

It is not clear why you are doing this, but I would call it "flattening" the array. If you find the need to do this often then creating a "worker" method might help.

For example, in a model, you might have two methods that both need "flat" results.

public function get_something()
{
    $query = $this->db->query("SELECT field_name FROM table_name;");
    //call the "worker"
    return $this->make_flat($query);
}

public function get_something_else()
{
    $query = $this->db->query("SELECT field_name FROM table_name;");
    //call the "worker"
    return $this->make_flat($query);
}

Elsewhere in the model, there is this "worker" method used in the code above used.

// The "worker" method to flatten the results
protected function make_flat($query)
{
    $getData = []; //is same as $getData = array(); but with less typing
    foreach ($query->result() as $row)
    {
        $getData[] = $row->field_name;
    }
    return $getData;
}

The line $getData[] = $row->field_name; does exactly the same thing as array_push($getData, $row->field_name); . But it is actually a bit faster. It is also less typing.

Answer 2

http://php.net/manual/en/function.array-column.php should work great for this.

$query = $this->db->query("SELECT field_name FROM table_name;");

$array = array_column($query, 'field_name');

print_r($array);

your question seems to contradict your code. if you just want to see if a particular entry already exists you can do:

$this->db->where('field_name', $var);
$exists = $this->db->count_all_results('table_name');
if ($exists > 0) {
    // update
    // there is an entry with $var for `field_name` in table `table_name`
} else {
    // insert
}