Zend Many to Many Relationship - database

I want to retrieve all the data from 3 tables
users , properties and users_properties.
So I decided I would use the manytomanyRowset. But to my surprise I get the data from the properties and users_properties table but no data from the users table. Why is that? I need some columns from the users table is there a way to tell the manytomanyrowset function that I need the data from the current table as well?
this is my function
public function fetchRegisteredProperties()
{
$userTable = $this->getTable();
require_once APPLICATION_PATH . '/models/DbTable/UsersPropertiesDB.php';
require_once APPLICATION_PATH . '/models/DbTable/PropertiesDB.php';
$propertiesRowset = $table->fetchAll();
$allProperties = array();
foreach ($propertiesRowset as $row) {
$propertiesRowset = $row->findManyToManyRowset(
'Model_DbTable_Properties','Model_DbTable_UsersProperties');
$allProperties = array_merge($tempArray,$propertiesRowset->toArray());
}
return $allProperties;
}
thanks in adavance

I designed and coded the table-relationships features in Zend Framework.
The answer to your question is no, the findManyToManyRowset() method only fetches rows from the related table, it does not merge them into the corresponding Row object. The reason is that a Row object in ZF can save() itself back to the database, and if you add fields it won't know what to do with them.
So you should implement a custom Row object to hold both user fields and the collection of user properties -- store the user properties as a Rowset object.
Then extend __get() and __set() so that it knows how to map fields into the correct array when you read or write object properties. That is, if one tries to read or write a field that isn't part of the user row, it falls back to the user properties Rowset.
Also extend save() to save not only the current row, but also call save() on the Rowset of user properties.

Related

Cakephp 3 - How to integrate external sources in table?

I working on an application that has its own database and gets user information from another serivce (an LDAP is this case, through an API package).
Say I have a tables called Articles, with a column user_id. There is no Users table, instead a user or set of users is retrieved through the external API:
$user = LDAPConnector::getUser($user_id);
$users = LDAPConnector::getUsers([1, 2, 5, 6]);
Of course I want retrieving data from inside a controller to be as simple as possible, ideally still with something like:
$articles = $this->Articles->find()->contain('Users');
foreach ($articles as $article) {
echo $article->user->getFullname();
}
I'm not sure how to approach this.
Where should I place the code in the table object to allow integration with the external API?
And as a bonus question: How to minimise the number of LDAP queries when filling the Entities?
i.e. it seems to be a lot faster by first retrieving the relevant users with a single ->getUsers() and placing them later, even though iterating over the articles and using multiple ->getUser() might be simpler.
The most simple solution would be to use a result formatter to fetch and inject the external data.
The more sophisticated solution would a custom association, and a custom association loader, but given how database-centric associations are, you'd probably also have to come up with a table and possibly a query implementation that handles your LDAP datasource. While it would be rather simple to move this into a custom association, containing the association will look up a matching table, cause the schema to be inspected, etc.
So I'll stick with providing an example for the first option. A result formatter would be pretty simple, something like this:
$this->Articles
->find()
->formatResults(function (\Cake\Collection\CollectionInterface $results) {
$userIds = array_unique($results->extract('user_id')->toArray());
$users = LDAPConnector::getUsers($userIds);
$usersMap = collection($users)->indexBy('id')->toArray();
return $results
->map(function ($article) use ($usersMap) {
if (isset($usersMap[$article['user_id']])) {
$article['user'] = $usersMap[$article['user_id']];
}
return $article;
});
});
The example makes the assumption that the data returned from LDAPConnector::getUsers() is a collection of associative arrays, with an id key that matches the user id. You'd have to adapt this accordingly, depending on what exactly LDAPConnector::getUsers() returns.
That aside, the example should be rather self-explanatory, first obtain a unique list of users IDs found in the queried articles, obtain the LDAP users using those IDs, then inject the users into the articles.
If you wanted to have entities in your results, then create entities from the user data, for example like this:
$userData = $usersMap[$article['user_id']];
$article['user'] = new \App\Model\Entity\User($userData);
For better reusability, put the formatter in a custom finder. In your ArticlesTable class:
public function findWithUsers(\Cake\ORM\Query $query, array $options)
{
return $query->formatResults(/* ... */);
}
Then you can just do $this->Articles->find('withUsers'), just as simple as containing.
See also
Cookbook > Database Access & ORM > Query Builder > Adding Calculated Fields
Cookbook > Database Access & ORM > Retrieving Data & Results Sets > Custom Finder Methods

How to apply a condition to a specific table in every request on Entity Framework?

I have a many-to-many structure mapped to entity framework. This is a sample of what it looks like:
User UserTag Tag
------- -------- -------
IdUser(PK) IdUserTag(PK) IdTag(PK)
Name IdUser(FK) TagName
Desc IdTag(FK) Active
Now, I needed to exclude from any request of any method the viewing of Tags that were Active=false.
First, I tried doing it manually in every method, like:
public User GetById(int id)
{
var item = UserRepository.GetById(id); //This is just a repository that calls the EF context
//EF automatically maps it to the *UserTags* property
foreach(var tag in item.UserTags)
{
if(tag.Tag.Active == false)
item.UserTags.Remove(tag);
}
}
But it throws the following exception:
The relationship could not be changed because one or more of the foreign-key properties is non-nullable
So, I wanted to know if there's a way to conditionaly filter every request made to a specific table, whether it is select or a join request.
Try this in your GetById method:
var user.UserTags = dbContext.Entry(user)
.Collection(u => u.UserTags)
.Query()
.Where(ut => ut.Active == true)
.ToList();
The supplied code fails because it is attempting to remove items from the data entities not the list. If you want to pass the data entity around instead of the data model, you need to not use Remove. Something like the below (untested should work).
tags = item.UserTags.Where((ut) => ut.Active).ToList();
This line will get you a list of data entities that are active. However, you should really map all of this into a data model (see AutoMapper) and then you would not be removing items from the database.

Symfony2 mapping between 3 entities

I have three entities : Event, Photo and User.
Three main relations :
An Event has 0 or more photos (blue relation, OneToMany)
An Event has been created by one photo, which I call the firstPhoto (red relation,
OneToOne)
A user can create 0 or more photos (violet relation,
OneToMany)
What I want is to map the relation between an Event and the User who created it, without adding or changing my database. It means the user that created the firstPhoto of the Event.
I'm not looking for a SQL query which I succed to do but really a mapping in my User.php Entity.
$user->getEvents() would give the events the user created.
I can't success to do so... any idea ? Am I obliged to add or change something in my database ?
I see 2 ways of doing that:
1) make a named native query http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/native-sql.html#named-native-query
2) write something like
public function getEvents()
{
$res = array();
$photos = $this->getPhotos();
foreach($photos as $photo) {
$res[] = $photo->getEvent();
}
return $res;
}

how to display the data returned by get_by_user_id() in DataMapper Code Igniter?

I am new to code igniter data mapper. I have a table called user, and I am trying to retrieve data from the database table and show them to the user.
Here is what I have in the model:
$u=new User();
$results=$u->get_by_user_id($id);
//$results here will be set to huge bunch of none sense data( which also includes the row that I am looking for as well)
if ($u->exists())
{
foreach ($results->all as $row){
$data['user']['first_name']=($row->user_first); //this where I am stuck ..
$data['user']['last_name']=($row->user_last);//this is also where I am stuck..
}
I don't know how to treat results to get a required fields I am looking for and store them in the $data I am passing to the user to view.
Thanks!
When you call get_by_x() on the model, the fields will be populated with data and you can access them like this:
$u = new User();
$u->get_by_user_id($id);
if($u->exists())
{
// you can access the table columns as object fields
$data['user']['first'] = $u->first;
$data['user']['last'] = $u->last;
}
else
{
$data['error'] = 'No such user!';
}
Have a look at the documentation which is really helpful: see Get and Get By.
Also, DataMapper expects all tables to have an id column: see Table Naming Rules. If your column is named id you should then call $u->get_by_id($id) instead of $u->get_by_user_id($id).

What is the equivalent to getLastInsertId() in Cakephp?

If I do getLastInsertId() immediately after a save(), it works, but otherwise it does not. This is demonstrated in my controller:
function designpage() {
//to create a form Untitled
$this->Form->saveField('name','Untitled Form');
echo $this->Form->getLastInsertId(); //here it works
}
function insertformname() {
echo $this->Form->getLastInsertId(); //this doesnt echo at all
}
Please suggest a way to get the functionality I want.
CakePHP has two methods for getting the last inserted id: Model::getLastInsertID() and Model::getInsertID().
Actually these methods are identical so it really doesn't matter which method you use.
echo $this->ModelName->getInsertID();
echo $this->ModelName->getLastInsertID();
This methods can be found in cake/libs/model/model.php on line 2768
Just use:
$this->Model->id;
In Cake, the last insert id is automatically saved in the id property of the model. So if you just inserted a user via the User model, the last insert id could be accessed via $User->id
id - Value of the primary key ID of
the record that this model is
currently pointing to. Automatically
set after database insertions.
Read more about model properties in the CakePHP API Docs: http://api.cakephp.org/2.5/class-AppModel.html
Edit: I just realized that Model::getLastInsertID() is essentially the same thing as Model->id
After looking at your code more closely, it's hard to tell exactly what you're doing with the different functions and where they exist in the grand scheme of things. This may actually be more of a scope issue. Are you trying to access the last insert id in two different requests?
Can you explain the flow of your application and how it relates to your problem?
You'll need to do an insert (or update, I believe) in order for getLastInsertId() to return a value. Could you paste more code?
If you're calling that function from another controller function, you might also be able to use $this->Form->id to get the value that you want.
Try using this code in your model class (perhaps in AppModel):
function get_sql_insert_id() {
$db =& ConnectionManager::getDataSource($this->useDbConfig);
return $db->lastInsertId();
}
Caveat emptor: MySql's LAST_INSERT_ID() function only works on tables with an AUTO_INCREMENT field (otherwise it only returns 0). If your primary key does not have the AUTO_INCREMENT attribute, that might be the cause of your problems.
this is best way to find out last inserted id.
$this->ModelName->getInsertID();
other way is using
$this->ModelName->find('first',array('order'=>'id DESC'))
There are several methods to get last inserted primary key id while using save method
$this->loadModel('Model');
$this->Model->save($this->data);
This will return last inserted id of the model current model
$this->Model->getLastInsertId();
$this->Model-> getInsertID();
This will return last inserted id of model with given model name
$this->Model->id;
This will return last inserted id of last loaded model
$this->id;
Try to use this code. try to set it to a variable so you can use it in other functions. :)
$variable = $this->ModelName->getLastInsertId();
in PHP native, try this.
$variable = mysqli_insert_id();
This will return last inserted id of last loaded model
$this->id;
This will return last inserted id of model with given model name
$this->Model->id;
This will return last inserted id of the model current model
CakePHP has two methods for getting the last inserted id:
Model::getLastInsertID() and Model::getInsertID().
echo $this->ModelName->getInsertID();
echo $this->ModelName->getLastInsertID();
Below are the options:
echo $this->Registration->id;
echo $this->Registration->getInsertID();
echo $this->Registration->getLastInsertId();
Here, you can replace Registration with your model name.
Thanks
Use this one
function designpage() {
//to create a form Untitled
$this->Form->saveField('name','Untitled Form');
echo $this->Form->id; //here it works
}
You can get last inseted id with many ways.Like Model name is User so best way to fetch the last inserted id is
$this->User->id; // For User Model
You can also use Model function but below code will return last inserted id of model with given model name for this example it will return User model data
$this->User->getLastInsertId();
$this->User->getInsertID();
When you use save(), the last insert ID is set to the model’s $id property. So:
if ($this->Model->save()) {
printf('Last insert ID was %s', $this->Model->id);
}
Each time a save method is called on a model, cake internally calls Model::getLastInsertId() and stores the result into model class attribute id, so after calling save() it is not necessary to call Model::getLastInsertId() or inserId(), as tha value can be directly accessed like this
$id = $this->id;// within a model
$id = $this->{$this->modelName}->id;// in a controller
After insertion of data, we can use following code to get recently added record's id:
$last_insert_id=$this->Model->id;
each time you perform an insert operation on any model, cake internally fetchesthe last insert Id and Sets to Model->id attribute.
so one can access it directly by $Model->id;,
no need to query again for lastInsertId.
I think it works with getLastInsertId() if you use InnoDB Tables in your MySQL Database. You also can use $this->Model->id
$Machinedispatch =
$this->Machinedispatch->find('first',array('order'=>array('Machinedispatch.id DESC')));
Simplest way of finding last inserted row. For me getLastInsertId() this not works.
Actually you are using the getLastInsertId or getInsertId in a wrong manner.
getLastInsertId() is meant to work only after save() method.
It will even not work after a manual insert, as cake engine is storing the mysql_insert_id under $this->_insertID inside the save method which can be retrieved via the getLastInsertId or getInsertId.
Now in your case
$this->Model->id
OR
$this->Model->find('first',array('order'=>'id DESC'))
Will do.
This is interesting, I also stumbled upon this issue. What you asked perhaps how to get the last ID of a certain model regardless of it's state, whether it's just been inserted or not. To further understand what getInsertID does, we need to take a look at the source:
Link 1: http://api20.cakephp.org/view_source/model#line-3375
public function getInsertID() {
return $this->_insertID
}
Yup, that's the only piece of code inside that function. It means that cakephp caches any last inserted ID, instead of retrieve it from the database. That's why you get nothing if you use that function when you haven't done any record creation on the model.
I made a small function to get the last ID of a certain table, but please note that this should not be used as a replacement of getLastID() or getLastInsertID(), since it has an entirely different purpose.
Add the function lastID() to the AppModel as shown below so that it can be used system wide. It has it's limit, which can't be used on model with composite primary key.
class AppModel extends Model {
public function lastID() {
$data = $this->find('first',
array(
'order' => array($this->primaryKey . ' DESC'),
'fields' => array($this->primaryKey)
)
);
return $data[$this->name][$this->primaryKey];
}
}
Original Source : Class Model
In CakePHP you can get it by:
Model::getInsertID() //Returns the ID of the last record this model inserted.
Model::getLastInsertID() //Alias to getInsertID().
$this->Model->field('id', null, 'id DESC')

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