I just confused because of a find() result. This is my configurations:
First, users can have different User.role values: student, admin, and some others.
// Book
public $belongsTo = array(
'Student' => array(
'className' => 'User',
'foreignKey' => 'student_id'
'conditions' => array('User.role' => 'student')
);
);
When I chain Models like $this->Book->Student->find('list'); I was expecting to get only users whose role are 'student', but instead, it gets all users. What is going on here, what is conditions for on association definition, where can it and cannot be used. Any lead would help, thanks.
PS: I am aware that I could put conditions on find(), that's not the issue
There is a difference between associated data and accessing an associated model object. If you access $this->Book->Student you're accessing the Student model and work in it's scope. The conditions in the defined associations work only in the context of the accessed object.
So if you do a find on the Book and list the students for that book:
$this->Book->find('first', array('contain' => array('Student'));
Your code will work correctly. It will find the book plus the first user who has the role stundent. BUT your association is wrong then: It should be hasMany. because why would you filter a book by role if the book just belongsTo one student?
If you want to filter users by their role you can implement a query param that is checked in beforeFind(), pseudocode: if isset roleFilter then add contention to filter by that role from roleFilter.
Or, if you don't need to paginate just create a getStudents() method in the user model that will return a find('list') that has the conditions.
Or Student extends User and put the filter in the beforeFind() and use that model instead of the User model in your Book association.
If you want to filter on model level or per model I think the last one is a good option. Don't forget to set $useTable and $name or the inherited model will cause problems.
you have miss , inside your model.
try this:
public $belongsTo = array(
'Student' => array(
'className' => 'User',
'foreignKey' => 'student_id', //<------ miss
'conditions' => array('User.role' => 'student')
);
);
Yoi can debug your query to check what is the real query that you make.
Personally I have never use this approach, I prefer to use foreign key with another table for examples Rolesand User.role_id.
Is better for me to use this approach to have more flexibility inside your app.
After I prefer to use a conditions where inside controller to check well the query, because in your way every query you search always for student role not for the other and can be a problem for the rest of role, because inside controller you see a find without conditions but it doesn't take right value because in your model there is a particular conditions.
For me the good way is to create a new table, use foreign key and where conditions inside action of the controller to view well what are you doing.
For default all relations are "left join", you must set the parameter "type" with "inner" value
// Book
public $belongsTo = array(
'Student' => array(
'className' => 'User',
'foreignKey' => 'student_id'
'conditions' => array('Student.role' => 'student'), // <-- Fix That (field name)
'type' => 'inner', // <-- add that
);
);
Related
My CakePHP Cart model/table has only one field: id.
It hasMany LineItems.
I am not having success saving the Cart model alone:
$this->Cart->create();
$this->Cart->save();
Or, by passing it a $data array structured as follows and using saveAssociated():
$data = array(
'Cart' => array(),
'LineItem' => array(
array(
'item_id' => $item_id,
'qty' => $qty,
'price_option_id' => $price_option_id
)
)
);
If I add a useless_field to the Cart table/model, and pass some data in it saves. So obviously the problem lies in my having a model with a table with just a single id field and not passing in any other data to save. It won't create what it must be assuming is an 'empty' record.
I have passed 'validate' => false into the saveAssociated call but it doesn't make a difference (and there are no validations for this model to ignore).
Is there a way to do this? Am I missing something? Please enlighten me!
CakePHP tables require created and modified fields, or for you to define your own fields (ie you can call them whatever you want but they do the same thing).
In this instance you would use
$this->Cart->set($data);
$this->Cart->saveAll();
Here is Yet another cakePHP question! I have table called blood_groups which has blood_group_id and group fields.. Then I have another table called donors, which has several fields such as name, surname etc. Another field included inside this table is the foreign key 'blood_group_id' which will need to map to the blood_group table on retrieval. in the donor registration view, i want to be able to retrieve the values from the blood_groups table, and display them using the formHelper (with their respective id's).
I have gone through CAKE doc, and I understand that I would need to create the association between my models, but I am struggling to figure this one out. Should I create $hasOne association inside the Donor Model (considering that the Donor table has the fk of the other table). And how would I go about retrieving the options of blood_groups from the blood_groups Model?
Should It work like this?(and are any other prerequisites involved?) :
In my DonorController -
$this->set('blood_groups', $this->Donor->Blood_Group->find('all'));
in Views/Donor/add.ctp
echo $this->Form->input('blood_group_id');
Accessing data through associations is fine. But for radios or checkboxes you want to do a find('list). Your model and variable name does not match the CakePHP convention, there should be no underscore.
Properly named this should be already enough to populate the input.
// controller
$this->set('bloodGroups', $this->Donor->BloodGroup->find('list'));
// view
echo $this->Form->input('blood_group_id');
If you don't follow the conventions for some reason:
echo $this->Form->input('blood_group_id', array(
'options' => $bloodGroups
));
See:
Linking Models Together
The Form Helper
Create one function in BloodGroup Model
function getDonors(){
$options = array(
// 'conditions' => array('Donor.blood_group_id'=>$id),
'joins' => array(
array(
'alias' => 'Donor',
'table' => 'donors',
'type' => 'LEFT',
'conditions' => array(
'Donor.blood_group_id = BloodGroup.blood_group_id',
),
)
),
'fields' => array('Donor.name','Donor.surname','Donor.blood_group_id',
'BloodGroup.blood_group_id')
);
$returnData = $this->find('all',$options);
return $returnData;
}
Now from controller call this function
App::import('model','BloodGroup');
$BloodGroup = new BloodGroup;
$donorList = $BloodGroup->getDonors();
$this->set('donorList',$donorList);
In view file you will get list of donors in $donorList.
Is it possible for a virtualFields var to be the sum of a field from a linked table?
For example, in, say, an Invoice model, could you have
public $virtualFields = array(
'invoiceNett' => 'SUM(InvoiceLine.nett)'
);
but obviously only SUMming the lines that belong to that invoice?
Thanks.
== Using CakePHP 2.0
You could use the afterFind callback to get the sum. This avoids storing the calculated values, which should be avoided when possible.
function afterFind($results)
{
foreach($results as &$result)
{
/*
Use something like:
$this->InvoiceLine->find('all', array('fields' => array('SUM(InvoiceLine.nett) as total'),
'conditions' => array('invoice_id' => $result['Invoice']['id'])));
*/
}
unset($result);
}
As far as I know, the best way to do that would be to have an actual total field, and update it anytime the data is saved (likely with a afterSave callback method).
So - anytime an InvoiceLine is saved, you run some code to update it's associated Invoice with a new total.
//InvoiceLine model
public function beforeSave() {
//code to update Invoice's "total" field
}
Theoretically, yes, if that linked table is an associate that is joined (belongsTo and hasOne).
However this would be a poor idea because if you decide not to include that table you would generate a SQL error.
You'd be better off having a separate function grab the data or creating a virtual field that was a nested SQL query.
Defining your virtual field in the respective Model would make more sense.
If not done so, you will be breaking the MVC pattern.
You can use that virtual field from other related models.
If you don't want using them in all related models, you can always use the field
attribute whilst defining relations.
public $hasMany = array(
'IwantVirtualField' => array(
'className' => 'MyModel',
...
)
);
In a model where you don't want virtual field
public $belongsTo = array(
'IwantVirtualField' => array(
'className' => 'MyModel1',
'fields' => array('MyModel1.id', 'MyModel1.name')
...
)
);
I read much about how great containable is. Honestly I have read all docs, I have it working in my Users controller, but some things are not clear:
Do I have to use it in All actions or only in Index()?
Do I have to define it in every controller index() function or is it enough to it once in the Users controller
What about if e.g. Country_ID is a FK connected to both user and a related model? For example:
function index() {
$this->paginate = array(
'limit'=>10,
'order'=>'User.created DESC',
'fields'=>array('User.id','User.name', 'User.country_id', 'User.email'),
'contain'=>array(
'Post',
'Company' => array(
'Country' => array(
'fields' => array('id', 'country')
)
),
'Position' => array(
'Profession'
),
'Preference',
'Country',
'Type'
),
);
$this->set('users',$this->Paginate('User'));
}
Country is both connected to User and Company. How to define this without creating duplicates?
Many thanks!
You seem to have the wrong idea about containable. It "allows you to filter and limit model find operations". You use it whenever you need include (or exclude) specific related model data in your find().
For example, a User hasOne Profile, hasMany Roles, which belongsTo a Company. And you need to get all the roles and related companies for a user, but you don't need the profile, you can use $this->User->find('first',array('conditions'=>...,'contain'=>array('Role'=>array('Company'))))
It has nothing to do with index() or users_controller.
Country is both connected to User and Company. How to define this without creating duplicates? What duplicates?
In my "Reports" controller, which is just a dummy controller without any actual database, I'm trying to generate a paginated view of other models. For example, to generate paginated view of "Transactions" model I'm doing the following:
$this->loadModel('Transactions');
$this->Transactions->bindModel(array('belongsTo'=>array('Item'=>array('className'=>'Item'),'Member'=>array('className'=>'Member'))));
$results = $this->paginate('Transactions',null,array('recursive'=>1));
But this is not giving me associated data from Items and Members. If I do a
$this->Transactions->find('all',array('recursive'=>1))
I get the associated data, but not paginated. How will I get paginated view which includes the associated data too?
Two things: First, even when plural model names can work for some odd reason, the convention is that model names are singular, like $this->loadModel('Transaction');. See the manual on naming conventions.
Second, forget about recursive and go for the Containable behavior. Frankly, it's so useful that I wonder why it isn't the default process (perhaps because Containable got created when the framework was very mature). Matt has a good book explaining why Containable is good (download it, really, it's almost mandatory :D ). But to help even more, I'm going to tell you exactly how you solve your issue with containable:
1) Define the associations in the models, like:
In Transaction model:
var $belongsTo = array(
'Item' => array(
'className' => 'Item',
'foreignKey' => 'item_id',
)
);
In Item model:
var $hasMany = array(
'Transaction' => array(
'className' => 'Transaction',
'foreignKey' => 'item_id',
'dependent' => true,
'exclusive' => true,
)
);
Do the same for the Member model.
2) Create an app_model.php file in /app/ with this code:
(The $actsAs variable here within the AppModel class tells all models to use Containable)
<?php
class AppModel extends Model {
var $recursive = -1;
var $actsAs = array('Containable');
}
?>
3) In the Reports Controller, change the code to something like this:
(The contain parameter is an array of all the associated models that you want to include. You can include only one assoc. model, or all, or whatever you want).
$this->loadModel('Transaction');
$this->paginate = array('Transaction' => array('contain' => array('Item', 'Member')));
$results = $this->paginate('Transaction');
And that's it!