DATE_FORMAT在笨活动记录的条件

Question

我想笨相当于下面的SQL：

select * from `table_name` where DATE_FORMAT('table_name', "%Y-%m") < "YYYY-MM" 

我都尝试过，但得到NULL作为answer.Here是我做到了

$this->db->select_sum('column_name')->from('table_name')->where("DATE_FORMAT('column_name','%Y-%m') <","YYYY-MM")->get(); 

Thnx有什么帮助吗？

Answer 1

使用没有引用column_name像DATE_FORMAT(column_name,'%Y-%m')

$this->db->select_sum('column_name') 
     ->from('table_name') 
     ->where("DATE_FORMAT(column_name,'%Y-%m') <","YYYY-MM") 
     ->get(); 

Answer 2

试试这个

$this->db->select_sum('column_name') 
      ->from('table_name') 
      ->where("DATE_FORMAT('column_name','%Y-%m') < YYYY-MM") 
      ->get(); 

您可以在手工编写自己的条款... read the docs

Answer 3

试试这个

$this->db->select("DATE_FORMAT(your_date_field, 'Year: %Y Month: %m Day: %d') AS formated_date"); 
$query = $this->db->get('your_table'); 

你只是去通过这个THREADS