PHP Data Libraries

notes.php

<?php

// This file contains comments that help you understand comparison
// criteria better: for "PHP Data Library comparison"

// http://socialcompare.com/en/comparison/php-data-access-libraries-orm-activerecord-persistence

// General Premise

// Data Access frameworks hide implementation detail of a specific database engine and allow you to work
// with data in an easier way. See also "Domain Model", "Persistence" and "Mapping".

// Legend

// GREEN: feature is natively supported or can be achieved in 1-2 lines of code or add-on.
// YELLOW: planned, has work-around or not relevant to the approach.
// RED: not supported or requires a hack.



// Entity Definition, using pseudo PHP:

class Client {
  public string $name; // label: Full Name
  public text $address;
  public bool $vip;
  public $invoices[];
}
  
class Invoices {
  public Client $client;
  public int $total;
  public $lines[];
}

class Line {
  public money $price;
  public int $qty;
  public money $total;
}

// Persistence Definition

$db = new Persistence_SQL($dsn);

$data = [];
$db_array = new Persistence_Array($data);

$db_mongo = new Persistence_MongoDB($connection);

$json = "[]";
$db_json = new Persistence_JSON($json);

/////////////////////////////////////////////////////////////////////////////////
// Same model, multiple persistences

/**
 * Persistence-agnostic code
 */
function loadUser($user_model) {
  return $user_model->loadBy('name', 'John');
}

$user_sql = new User($db);
$user_array = new User($db_array);
                     

//////////////////////////////////////////////////////////////////////////////////
// Vendor-specific extensions

function getStats($user_model) {
  if ($user_model->persistence instanceof Persistence_Mongo) {
    $user_model->aggregate(...);
  } else {
    foreach ($user_model ..) {
      ..
    }
  }
}

////////////////////////////////////////////////////////////////////////
// Table Name, Field, etc mapping

$user_sql = new User($db, 'app_user_table');
$user_sql->name.actual_sql_column = 'full_name';

echo $user_sql->name;   // shows full_name.

////////////////////////////////////////////////////////////////////////
// Map Entity to SubQuery

$user.table = 'call get_user_list()';

////////////////////////////////////////////////////////////////////////
// Native field mapping

var_dump($user->birth_date); // <-- DateTime object

///////////////////////////////////////////////////////////////////////
// User Defined Types

$line->total = [259.29, 'EUR'];
$line->save();
// stores into "total_amount" and "total_currency"

///////////////////////////////////////////////////////////////////////
// related Entity field

$invoice->load(2);  // single query
echo $invoice->client->name; // no extra query!

///////////////////////////////////////////////////////////////////////
// sub-query on Related Entity

$invoice->load(2);
echo $invoice->total; // sum(amount) from line where invoice_id = 2

///////////////////////////////////////////////////////////////////////
// Entity to join multiple tables

$client->load(2);
$client->name = 'John';
$client->address = '29 Street';
$client->save();

// UPDATE client set name = 'John'
// UPDATE client_address set address = '29 Street'


// Criteria is a permanent condition on a domain model, that must
// be true at all times.


////////////////////////////////////////////////////////////////////////
// Soft Delete

$client->load(2); // record not found. Actually it's there but marked as deleted.
// criteria condition didn't match.

////////////////////////////////////////////////////////////////////////
// Domain Model Criteria

$vip_client = new VipClient();
$vip_client->name='Peter';
$vip_client->save();

// INSERT into client name='Peter', vip=1, deleted=0

////////////////////////////////////////////////////////////////////////
// Criteria compliance

$vip_client = new VipClient();
$vip_client->name='Peter';
$vip_client->vip = false;
$vip_client->save();   // fails! only vip clients!

////////////////////////////////////////////////////////////////////////
// Expression conditions

class ClientWithCondition {
  public $name;
  public $surname;
  condition $name=$surname;
}

$c = new ClientWithCondition();
$c->load(2); // where id = 2 and name = surname

/////////////////////////////////////////////////////////////////////////
// Dynamic Condition

$id = $_GET['order_id'];

$c = new AccessibleOrder();
$c->load($id);
// where id = 2 and client_id = 39 <-- due to user authentication

/////////////////////////////////////////////////////////////////////////
// Convert Model into Query

$order = new AccessibleOrder();
$query = $order->getUpdateQuery();

$query->set('is_shipped', false)->update();
// update order set is_shipped where client_id = 39 <-- due to authentication