How can I SELECT from multiple tables in CodeIgniter - mysql

Question

I have three tables: (to keep it simple I'll only show the relevant fields)
Articles (id, title, text, author)
Comments (id, article_id, text, author)
Users (user_id, user_type, first_name, last_name, email, password)
In the articles table, because an author can have multiple articles, I only store the author's user_id from the users table, and I do the same for the comments table.
My problem is when I run an ActiveRecord query in the articles_model to get all articles along with that articles associated comments, and then echo the author in my view with $row->author, I only get the author's user_id which is 1, 2, 3, etc etc.
How do I go into the users table (different table) in that same query and get the authors actual first_name and last_name and return that?
Here's my code:
Controller:
$data['articles'] = $this->getArticles();
$this->load->view('articles_view', $data);
function getArticles() {
$this->load->model('articles_model');
$articles = $this->articles_model->getAllArticles();
return $articles;
}
articles_model:
function getAllArticles() {
$this->db->where('id', $this->uri->segment(3));
$query = $this->db->get('articles');
return $query;
}
articles_view:
<?php foreach($articles->result() as $row) { ?>
<?php echo $row->author ?>
<?php echo $row->text ?>
<?php } ?>
I have a ton of other fields, but this is an extremely stripped down version for simplicity's sake.
If I echo the above $row->author, I'm only going to get the user_id. I need to get the user's name from the users table instead. Surely I don't have to do another separate function call and pass more information into the view. Any help here would be greatly appreciated and would actually open up a world for me :)

Answer 1

Try this (or just have an idea):
I assumed that user_id from your users table is foreign key of articles and comments table since you said that the authors and commentators user_id are stored in users table.
On your controller:
$data['articles'] = $this->getArticles();
$this->load->view('articles_view', $data);
function getArticles() {
$this->load->model('articles_model');
$articles = $this->articles_model->getArticlesById();
return $articles;
}
On your model:
// this will get the article of a certain author
function getArticlesById()
{
$this->db->where('id', $this->uri->segment(3));
$q = $this->db->get('articles');
if($q->num_rows() > 0)
{
$q = $q->row_array();
$result = $this->getCommentsAndAuthors($row);
return $result;
}
return 0;
}
// this will get the comments of each articles of the author and the author of the comments
function getCommentsAndAuthors($row)
{
$result = $data = array();
$this->db->select('c.*, u.firstname, u.lastname');
$this->db->from('users u');
$this->db->where('u.id', $row['user_id']);
$this->db->join('comments c', 'c.id = u.id');
$q = $this->db->get();
foreach($q->result_array() as $col)
{
$data[] = $col;
}
$result['article'] = $row;
$result['comments'] = $data;
return $result;
}
I'm not sure if its work but that's the idea.

Answer 2

I have found a solution that works well for me which I will post and try to explain.
My Controller is like this:
function fullArticle()
{
$data['article'] = $this->getArticleDetail();
$data['comments'] = $this->getNewsTrendsComments();
$this->load->view('inner_view', $data);
}
function getArticleDetail()
{
$this->load->model('articles_model');
$articles = $this->articles_model->getArticles();
return $articles;
}
function getComments()
{
$this->load->model('articles_model');
$comments = $this->articles_model->getComments();
return $comments;
}
articles_model:
function getArticles()
{
$this->db->where('id', $this->uri->segment(3));
$query = $this->db->get('articles');
return $query;
}
function getComments()
{
$this->db->select('*');
$this->db->from('comments w');
$this->db->where('article_id', $this->uri->segment(3));
$this->db->join('users wc','w.author = wc.user_id');
$data = $this->db->get();
return $data;
}
As you can see, the getComments function in my model was the key. It's the JOIN statement that handles what I was trying to accomplish. I know there are probably cleaner and more efficient ways to do this, by combining the two functions, but as a beginner I wanted to keep it easier to understand.
Hopefully this can help others.