mysql - 将 mysql 查询转换为 CodeIgniter $query->row

Question

如何将此查询转换为 CodeIgniter？

$date = '28-05-2019';
$time_start = '10:00';
$time_end = '19:00';

select courtrooms.* from courtrooms
left join reservations 
on courtrooms.id = reservations.courtroom_id
and reservations.date = '$date' and reservations.time_start < '$time_start' and reservations.time_end > '$time_end'
where reservations.id is null

Answer 1

实际上有多种方法可以在 Codeigniter 中编写查询，如果您刚刚开始使用此框架编写查询，那么从我的角度来看，以下语法是最容易理解的。

请参阅Query Builder Class

$this->db->select('*');
$this->db->from('courtrooms');
$this->db->join('reservations','courtrooms.id = reservations.courtroom_id','left');
$this->db->where('reservations.id IS NULL', null, false);
$this->db->where('reservations.date', $date); 
$this->db->where('reservations.time_start<', $time_start);
$this->db->where('reservations.time_end>', $time_end);
$query = $this->db->get();

$query = $query->result();

上面的代码与下面的代码相同:

$query = $this->db->join('reservations','courtrooms.id = reservations.courtroom_id','left')
                  ->where('reservations.id IS NULL', null, false)
                  ->where('reservations.date', $date)
                  ->where('reservations.time_start<', $time_start)
                  ->where('reservations.time_end>', $time_end)
                  ->get('courtrooms');
$query = $query->result();