Class Aggregate

Provides streamlined access to a virtually unlimited number of data fields for a pre-defined conditional. Different data fields are actually stored as separate rows with the field name being a value of the configured column key.

Tabular storage has a similar structure as follows:

An aggregator is created with a conditional that requires ID = 1. The key column name is set to Key. The resulting instance allows simple data field access to the fields A, B and C which all yield an array with indices Value1 and Value2, each with their text values from the example table columns, respectively. If a new virtual data field D is set, the aggregator will automatically create a new storage entry with Key set to D for ID being set to 1.

If no access to multiple values per data field is required, subclasses can simply overwrite the getter and setter methods to instead work with a single value. An example implementation of a model that allows an arbitrary number of settings for a fixed user_id is as follows. The storage back-end table has only three columns, user_id, key and value:

class UserSettings extends \Core\Storage\Field\Aggregate

{
 const ReferenceName = 'user_settings';
 const ValueName = 'value';

 public function __construct($userID)
 {
 parent::__construct(
 // Every user has a unique user ID.
 db::eq(db::key('user_id'), $userID),
 // The user ID is the only template value required to add new entries.
 array ( 'user_id' => $userID ),
 );
 }

 public function getDataForKey($key)
 {
 $valueSet = parent::getDataForUndefinedKey($key);

 if (isset ($valueSet[static::ValueName])) {
 return $valueSet[static::ValueName];
 }

 return null;
 }
 public function setDataForKey($key, $value)
 {
 return parent::setDataForKey($key, array ( static::ValueName => $value ));
 }

}