循环不正确

Question

所以我访问数据库以检索员工 ID 列表，然后使用该员工 ID 数组对数据库上的另一个表运行查询，该表根据员工 ID 获取该人的所有信息，但我是只获取语句中的最后一个值，但我需要获取并循环所有这些值。谁能看到我的错误？

public function manager_list()
{
    $results = array();
    $managers = $this->db->query('select `employee_id` from `managers`');

    foreach($managers->result() as $row)
    {
        $employee_id = $row->employee_id;
    }

        $query = $this->db->query('select `employee_id`, `ssn`, `first_name`, `last_name`, `department`, `title`, `status` from `employees` where `employee_id` = "'.$employee_id.'"');

        foreach ($query->result() as $row){
            $results[] = array(
            'employee_id' => $row->employee_id,
            'ssn' => $row->ssn,
            'first_name' => $row->first_name,
            'last_name' =>$row->last_name,
            'department' =>$row->department,
            'title' =>$row->title,
            'status' =>$row->status,
        );
        }
    return $results; 
}

这是使用代码点火器框架。

Answer 1

如果您在单个查询中执行此操作，则可以进一步缩短它，但由于您说您必须有两个，这里是您的第二个查询的简短版本，不需要 foreach 循环：罢工>

$query = $this->db->query('
select `employee_id`, `ssn`, `first_name`, 
       `last_name`, `department`, `title`, `status` 
from `employees` where `employee_id` = "'.$employee_id.'"');

return $query->result_array(); 

使用活动记录：

return $this->db
->select('`employee_id`, `ssn`, `first_name`, 
       `last_name`, `department`, `title`, `status`')
->where(array('employee_id' => $employee_id))
->get('employees')
->result_array();

---

更新

这是一个带有 JOIN 的简短版本（替换您的整个代码）：

public function manager_list()
{
    return $this->db
    ->select('e.employee_id, e.ssn, e.first_name, 
              e.last_name, e.department, e.title, e.status')
    ->join('managers AS m', 'e.employee_id = m.employee_id')
    ->where(array('e.employee_id' => $employee_id))
    ->get('employees AS e')
    ->result_array();
}

Answer 2

使用 JOIN 执行一次查询并执行一次循环 -

public function manager_list()
{
    $results = array();
    $managers = $this->db->query('SELECT `m`.`employee_id`, `e`.`ssn`, `e`.`first_name`, `e`.`last_name`, `e`.`department`, `e`.`title`, `e`.`status` FROM `managers` AS `m` JOIN `employees` AS `e` ON `m`.`employee_id` = `e`.`employee_id`');

    foreach ($managers->result() as $row){
        $results[] = array(
            'employee_id' => $row->employee_id,
            'ssn' => $row->ssn,
            'first_name' => $row->first_name,
            'last_name' =>$row->last_name,
            'department' =>$row->department,
            'title' =>$row->title,
            'status' =>$row->status,
        );
    }
    return $results;
}