CodeIgniter:在CodeIgniter中使用group_by

Question

我有一个带有"user_name“和”post“的数据库。如何使用CodeIgniter的db类计算每个用户名的帖子数？

在SQL中：

SELECT 
  user_name, 
  COUNT(1) as post_count
FROM posts_by_user
GROUP BY user_name

在CodeIgniter中：

$this->db->select('user_name', ???????);
$this->db->from('posts_by_user');
$this->db->group_by('user_name');
$result = $this->db->query();

Answer 1

试一试

$this->db->select('user_name, COUNT(*) as cnt', FALSE);
$this->db->from('posts_by_user');
$this->db->group_by('user_name');
$result = $this->db->get();

return $result->result();