cakephp find(all) optimization - cakephp

Question

I am using cakephp 2.5.2
I have 5 tables
1- users
2- projects
3- tags
4- project_tags
5- images
a user can have many projects
a project can have many (tags,images)
I have 2 questions
$projects = $this->Project->find('all',array('conditions'=>array('User.id'=>$this->Auth->user('id'))));
debug($projects);exit();
this gives
array(
(int) 0 => array(
'Project' => array(
'id' => '1',
'name' => 'project 1'
),
'User' => array(
'password' => '*****',
'id' => '1',
'name' => 'User 1',
'email' => 'user1#gmail.com'
),
'Image' => array(),
'ProjectTag' => array(
(int) 0 => array(
'id' => '1',
'project_id' => '1',
'tag_id' => '1'
),
(int) 1 => array(
'id' => '2',
'project_id' => '1',
'tag_id' => '8'
),
(int) 2 => array(
'id' => '3',
'project_id' => '1',
'tag_id' => '6'
),
(int) 3 => array(
'id' => '4',
'project_id' => '1',
'tag_id' => '10'
),
(int) 4 => array(
'id' => '5',
'project_id' => '1',
'tag_id' => '4'
)
)
),
(int) 1 => array(
'Project' => array(
'id' => '2',
'name' => 'project 2'
),
'User' => array(
'password' => '*****',
'id' => '1',
'name' => 'user 1',
'email' => 'user1#gmail.com'
),
'Image' => array(),
'ProjectTag' => array(
(int) 0 => array(
'id' => '6',
'project_id' => '2',
'tag_id' => '1'
),
(int) 1 => array(
'id' => '7',
'project_id' => '2',
'tag_id' => '8'
),
(int) 2 => array(
'id' => '8',
'project_id' => '2',
'tag_id' => '4'
)
)
)
)
I need Project & ProjectTag array while do not want user and images array
I tried recursive -1,0,1,2 but could not get what I needed
My Question Number 2 is
How can I find projects which has tag = 'html'
$projects = $this->Project->find('all',array('conditions'=>array('Tag.tag'=>'HTML')));
it says
Error: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'Tag.tag' in 'where clause'

Answer 1

First off, just a note. ALWAYS use $recursive=-1;. It's ideal just to set this in the AppModel, then never mess with recursive again. If you want to get additional data, use CakePHP's Containable Behavior, not recursive.
Overall issue - you cannot add conditions against a recursive (or contained) model, which is what you appear to be doing in both of your questions. If you want to condition against a model other than the one you're doing the find on, you need to either use JOINs or swap your query to run on the other model.
Answer to Question 1
Change this:
$projects = $this->Project->find('all',array(
'conditions'=>array(
'User.id'=>$this->Auth->user('id')
)
));
To this:
$projects = $this->Project->find('all',array(
'conditions'=>array(
'user_id'=>$this->Auth->user('id') // <-- notice this
),
'contain' => array(
'ProjectTag' => array(
'Tag' // <-- optional, as you didn't mention you needed
)
)
));
Answer to Question 2:
There are a number of ways to do this. I would suggest this one using joins:
$projects = $this->Project->find('all', array(
'fields' => array(
'Project.*',
'Tag.*'
),
'joins'=>array(
array(
'table' => 'tags',
'alias' => 'Tag',
'type' => 'inner',
'conditions' => array(
'Tag.project_id = Project.id',
'Tag.tag' => 'HTML'
)
)
)
));
Another way would be to swap your query to run on Tags and just use contain to contain the projects for that tag. I like the join better because if you ever way to extend it to retrieve projects for more than just one tag, your data will still be in an easy-to use manner, as opposed to Containable, which would put your projects in different arrays under their corresponding tag.

Answer 2

If you want to optimize your queries in CakePHP, turn off recursive (set it to -1), then use the containable behavior to pick and choose exactly which data you need.
As for your specific query, associated models are by default gotten by left joins, which means if you did your query from projects, you will get all projects plus any tags they have that have "html" in their tag field. The easiest way to fix this problem, is to do your search from tags instead:
$tags = $this->Tag->find('first', array('conditions' => array('tag' => 'html'), 'contain' => array('Project')));
This will get the tag that has 'html' for its tag field, and all the projects associated with it.