codeigniter中的活动记录会自动在where子句值周围添加引号

Question

I've tried reading other posts on stackoverflow and also checked the active record documentation for ci, but i can't seem to find the answer to my question

I have the following logic in my model:

    $query = $this->db->get_where('categories', array('parent_id' => $category_id));

the sql this generates as per the last_query() method is:

SELECT * FROM ( categories ) WHERE parent_id = '8'

I need to remove the quotes around the number 8. How would I do that?

I've tried using the select statement and passing false as the second parm. So for example:

    $this->db->select('*', false);
    $this->db->from('categories');
    $this->db->where('parent_id=',$category_id);

But that didn't really change much. Any suggestions? Thank you

Answer 1

By default, CodeIgniter tries to predict the data type in your comparison, and use the appropriate SQL syntax accordingly. If your query is using single quotes, it might indicate that $category_id is being treated as a string rather than an integer. What happens if you try:

$this->db->select('*');
$this->db->from('categories');
$this->db->where('parent_id', (int) $category_id);

Alternatively, you can construct your own WHERE statement manually:

$this->db->where('parent_id = ' . (int) $category_id);

Answer 2

For MIN and MAX query I used null and false keyword to remove the quotes.

$this->db->where("$value > min_column",null,false);
$this->db->where("$value < max_column",null,false);

Answer 3

The idea of the methods is to auto escape to protect against SQL injections, if for some reason you don't want to you can send a raw query like this :

$q = "select * from categories where parent_id = $category_id";
$this->db->query($q)->result();

Which i find much easier. However i think you can send an extra false paremeter to disable it, something like :

  $query = $this->db->get_where('categories', array('parent_id' => $category_id),false);

FYI, if you want to send raw queries and escape them(for more complex queries) you can use :

$category_id = $this->db->escape($category_id);