## Class TActiveRecord

Description

Base class for active records.

An active record creates an object that wraps a row in a database table or view, encapsulates the database access, and adds domain logic on that data.

Active record objects are stateful, this is main difference between the TActiveRecord implementation and the TTableGateway implementation.

The essence of an Active Record is an object model of the domain (e.g. products, items) that incorporates both behavior and data in which the classes match very closely the record structure of an underlying database. Each Active Record is responsible for saving and loading to the database and also for any domain logic that acts on the data.

The Active Record provides methods that do the following:

1. Construct an instance of the Active Record from a SQL result set row.
2. Construct a new instance for later insertion into the table.
3. Finder methods to wrap commonly used SQL queries and return Active Record objects.
4. Update the database and insert into it the data in the Active Record.

Example:

     class UserRecord extends TActiveRecord
     {
         const TABLE='users'; //optional table name.

         public $username; //corresponds to the fieldname in the table
              public $email;

         //returns active record finder instance
              public static function finder($className=__CLASS__)
         {
             return parent::finder($className);
         }
     }

     //create a connection and give it to the ActiveRecord manager.
      $dsn = 'pgsql:host=localhost;dbname=test';
     $conn = new TDbConnection($dsn, 'dbuser','dbpass');
     TActiveRecordManager::getInstance()->setDbConnection($conn);

     //load the user record with username (primary key) 'admin'.
      $user = UserRecord::finder()->findByPk('admin');
     $user->email = 'admin@example.org';
     $user->save(); //update the 'admin' record.

Since v3.1.1, TActiveRecord starts to support column mapping. The physical column names (defined in database) can be mapped to logical column names (defined in active classes as public properties.) To use this feature, declare a static class variable COLUMN_MAPPING like the following:

     class UserRecord extends TActiveRecord
     {
         const TABLE='users';
         public static $COLUMN_MAPPING=array
         (
             'user_id'=>'username',
             'email_address'=>'email',
         );
         public $username;
         pulbic $email;
     }

In the above, the 'users' table consists of 'user_id' and 'email_address' columns, while the UserRecord class declares 'username' and 'email' properties. By using column mapping, we can regularize the naming convention of column names in active record.

Since v3.1.2, TActiveRecord enhanced its support to access of foreign objects. By declaring a public static variable RELATIONS like the following, one can access the corresponding foreign objects easily:

     class UserRecord extends TActiveRecord
     {
         const TABLE='users';
         public static $RELATIONS=array
         (
             'department'=>array(self::BELONGS_TO, 'DepartmentRecord', 'department_id'),
             'contacts'=>array(self::HAS_MANY, 'ContactRecord', 'user_id'),
         );
     }

In the above, the users table is related with departments table (represented by DepartmentRecord) and contacts table (represented by ContactRecord). Now, given a UserRecord instance $user, one can access its department and contacts simply by: $user->department and $user->contacts. No explicit data fetching is needed. Internally, the foreign objects are fetched in a lazy way, which avoids unnecessary overhead if the foreign objects are not accessed at all.

Since v3.1.2, new events OnInsert, OnUpdate and OnDelete are available. The event OnInsert, OnUpdate and OnDelete methods are executed before inserting, updating, and deleting the current record, respectively. You may override these methods; a TActiveRecordChangeEventParameter parameter is passed to these methods. The property TActiveRecordChangeEventParameter::setIsValid of the parameter can be set to false to prevent the change action to be executed. This can be used, for example, to validate the record before the action is executed. For example, in the following the password property is hashed before a new record is inserted.

     class UserRecord extends TActiveRecord
     {
          function OnInsert($param)
          {
              //parent method should be called to raise the event
              parent::OnInsert($param);
              $this->nounce = md5(time());
              $this->password = md5($this->password.$this->nounce);
          }
     }

- abstract:
- since: 3.1
- version: $Id: TActiveRecord.php 2392 2008-03-07 17:01:44Z xue $
- author: Wei Zhuo <weizho[at]gmail[dot]com>

Located in /Data/ActiveRecord/TActiveRecord.php (line 137)

    TComponent
       |
       --TActiveRecord

Class Constant Summary
BELONGS_TO = 'BELONGS_TO'
HAS_MANY = 'HAS_MANY'
HAS_ONE = 'HAS_ONE'
MANY_TO_MANY = 'MANY_TO_MANY'
STATE_DELETED = 2
STATE_LOADED = 1
STATE_NEW = 0
Variable Summary
array $COLUMN_MAPPING
array $RELATIONS
integer $_recordState
Method Summary
TActiveRecord __construct ([array $data = array()], [TDbConnection $connection = null])
void copyFrom (mixed $data)
int count ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])
TActiveRecord createRecord (string $type, array $data)
TActiveRecordRelationContext createRelationContext (string $name)
boolean delete ()
int deleteAll ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])
void deleteAllByPks (mixed $keys)
int deleteByPk (mixed $keys)
boolean equals (TActiveRecord $record, [boolean $strict = false])
boolean fetchResultsFor (string $property)
TActiveRecord find (string|TActiveRecordCriteria $criteria, [mixed $parameters = array()])
array findAll ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])
array findAllByIndex (TActiveRecordCriteria $criteria, array $fields, array $values)
array findAllByPks (mixed $keys)
array findAllBySql (string $sql, [array $parameters = array()])
TActiveRecord. findByPk (mixed $keys)
TActiveRecord, findBySql (string $sql, [array $parameters = array()])
TActiveRecord finder ([string $className = __CLASS__])
void getActiveDbConnection ()
mixed getColumnValue (string $columnName)
TDbConnection getDbConnection ()
TSqlCriteria getRecordCriteria (string|TSqlCriteria $criteria, mixed $parameters, [array $args = array()])
TActiveRecordGateway getRecordGateway ()
TActiveRecordManager getRecordManager ()
array getRecordRelation (string $property)
array getRecordRelations ()
TActiveRecordRelation, getRelationHandler (string $name, [array $args = array()])
boolean hasRecordRelation (string $property)
void onCreateCommand (TDataGatewayEventParameter $param)
void onDelete (TActiveRecordChangeEventParameter $param)
void onExecuteCommand (TDataGatewayResultEventParameter $param)
void onInsert (TActiveRecordChangeEventParameter $param)
void onUpdate (TActiveRecordChangeEventParameter $param)
TActiveRecord populateObject (array $data)
array populateObjects (TDbDataReader $reader)
boolean save ()
void setColumnValue (string $columnName, mixed $value)
void setDbConnection (TDbConnection $connection)
mixed __call (mixed $method, mixed $args)
mixed __get (string $name)
void __set (string $name, mixed $value)
void __sleep ()
void __wakeup ()
Variables
array $COLUMN_MAPPING = array() (line 162)

This static variable defines the column mapping.

The keys are physical column names as defined in database, and the values are logical column names as defined as public variable/property names for the corresponding active record class.

- var: column mapping. Keys: physical column names, values: logical column names.
- static:
- access: public
- since: 3.1.1

array $RELATIONS = array() (line 172)

This static variable defines the relationships.

The keys are public variable/property names defined in the AR class. Each value is an array, e.g. array(self::HAS_MANY, 'PlayerRecord').

- var: relationship.
- static:
- access: public
- since: 3.1.1

integer $_recordState (line 152)

- var: record state: 0 = new, 1 = loaded, 2 = deleted.
- access: protected
- since: 3.1.2

Methods
Constructor __construct (line 205)

Create a new instance of an active record with given $data. The record can be saved to the database specified by the $connection object.

- access: public

TActiveRecord __construct ([array $data = array()], [TDbConnection $connection = null])

- array $data: optional name value pair record data.
- TDbConnection $connection: optional database connection this object record use.

copyFrom (line 282)

Copies data from an array or another object.

- access: public
- throws: TActiveRecordException if data is not array or not object.

void copyFrom (mixed $data)
count (line 676)

Find the number of records.

- return: number of records.
- access: public

int count ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])

- string|TActiveRecordCriteria $criteria: SQL condition or criteria object.
- mixed $parameters: parameter values.

createRecord (line 525)

Create an AR instance specified by the AR class name and initial data.

If the initial data is empty, the AR object will not be created and null will be returned. (You should use the "new" operator to create the AR instance in that case.)

- return: the initialized AR object. Null if the initial data is empty.
- static:
- access: public
- since: 3.1.2

TActiveRecord createRecord (string $type, array $data)

- string $type: the AR class name
- array $data: initial data to be populated into the AR object.

createRelationContext (line 711)

Gets a static copy of the relationship context for given property (a key in $RELATIONS), returns null if invalid relationship. Keeps a null reference to all invalid relations called.

- return: object containing information on the active record relationships for given property, null if invalid relationship
- access: protected
- since: 3.1.2

TActiveRecordRelationContext createRelationContext (string $name)

- string $name: relationship/property name corresponding to keys in $RELATION array.

delete (line 420)

Deletes the current record from the database. Once deleted, this object can not be saved again in the same instance.

- return: true if the record was deleted successfully, false otherwise.
- access: public

boolean delete ()
deleteAll (line 484)

Delete multiple records using a criteria.

- return: number of records deleted.
- access: public

int deleteAll ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])

- string|TActiveRecordCriteria $criteria: SQL condition or criteria object.
- mixed $parameters: parameter values.

deleteAllByPks (line 472)

Alias for deleteByPk()

- access: public

void deleteAllByPks (mixed $keys)
deleteByPk (line 462)

Delete records by primary key. Usage:

     $finder->deleteByPk($primaryKey); //delete 1 record
      $finder->deleteByPk($key1,$key2,...); //delete multiple records
      $finder->deleteByPk(array($key1,$key2,...)); //delete multiple records

For composite primary keys (determined from the table definitions):

     $finder->deleteByPk(array($key1,$key2)); //delete 1 record

     //delete multiple records
      $finder->deleteByPk(array($key1,$key2), array($key3,$key4),...);

     //delete multiple records
      $finder->deleteByPk(array( array($key1,$key2), array($key3,$key4), .. ));

- return: number of records deleted.
- access: public

int deleteByPk (mixed $keys)

- mixed $keys: primary key values.

equals (line 328)

Compare two records using their primary key values (all column values if table does not defined primary keys). The default uses simple == for comparison of their values. Set $strict=true for identity comparison (===).

- return: true if $record equals, false otherwise.
- access: public

boolean equals (TActiveRecord $record, [boolean $strict = false])

- TActiveRecord $record: another record to compare with.
- boolean $strict: true to perform strict identity comparison

fetchResultsFor (line 757)

Tries to load the relationship results for the given property. The $property value should correspond to an entry key in the $RELATION array.

This method can be used to lazy load relationships.

     class TeamRecord extends TActiveRecord
     {
         ...

         private $_players;
         public static $RELATION=array
         (
             'players' => array(self::HAS_MANY, 'PlayerRecord'),
         );

         public function setPlayers($array)
         {
             $this->_players=$array;
         }

         public function getPlayers()
         {
             if($this->_players===null)
                 $this->fetchResultsFor('players');
             return $this->_players;
         }
     }
     Usage example:
     $team = TeamRecord::finder()->findByPk(1);
     var_dump($team->players); //uses lazy load to fetch 'players' relation

- return: true if relationship exists, false otherwise.
- access: protected
- since: 3.1.2

boolean fetchResultsFor (string $property)

- string $property: relationship/property name corresponding to keys in $RELATION array.

find (line 551)

Find one single record that matches the criteria.

Usage:

     $finder->find('username = :name AND password = :pass',
                         array(':name'=>$name, ':pass'=>$pass));
     $finder->find('username = ? AND password = ?', array($name, $pass));
     $finder->find('username = ? AND password = ?', $name, $pass);
     //$criteria is of TActiveRecordCriteria
      $finder->find($criteria); //the 2nd parameter for find() is ignored.

- return: matching record object. Null if no result is found.
- access: public

TActiveRecord find (string|TActiveRecordCriteria $criteria, [mixed $parameters = array()])

- string|TActiveRecordCriteria $criteria: SQL condition or criteria object.
- mixed $parameters: parameter values.

findAll (line 566)

Same as find() but returns an array of objects.

- return: matching record objects. Empty array if no result is found.
- access: public

array findAll ([string|TActiveRecordCriteria $criteria = null], [mixed $parameters = array()])

- string|TActiveRecordCriteria $criteria: SQL condition or criteria object.
- mixed $parameters: parameter values.

findAllByIndex (line 664)

Fetches records using the sql clause "(fields) IN (values)", where fields is an array of column names and values is an array of values that the columns must have.

This method is to be used by the relationship handler.

- return: matching active records. Empty array is returned if no result is found.
- access: public

array findAllByIndex (TActiveRecordCriteria $criteria, array $fields, array $values)

- TActiveRecordCriteria $criteria: additional criteria
- array $fields: field names to match with "(fields) IN (values)" sql clause.
- array $values: matching field values.

findAllByPks (line 612)

Find multiple records matching a list of primary or composite keys.

For scalar primary keys:

     $finder->findAllByPk($key1, $key2, ...);
     $finder->findAllByPk(array($key1, $key2, ...));

For composite keys:

     $finder->findAllByPk(array($key1, $key2), array($key3, $key4), ...);
     $finder->findAllByPk(array(array($key1, $key2), array($key3, $key4), ...));

- return: matching ActiveRecords. Empty array is returned if no result is found.
- access: public

array findAllByPks (mixed $keys)

- mixed $keys: primary keys

findAllBySql (line 644)

Find records using full SQL, returns corresponding record object.

The names of the column retrieved must be defined in your Active Record class.

- return: matching active records. Empty array is returned if no result is found.
- access: public

array findAllBySql (string $sql, [array $parameters = array()])

- array $parameters
- string $sql: select SQL

findByPk (line 587)

Find one record using only the primary key or composite primary keys. Usage:

     $finder->findByPk($primaryKey);
     $finder->findByPk($key1, $key2, ...);
     $finder->findByPk(array($key1,$key2,...));

- return: Null if no result is found.
- access: public

TActiveRecord. findByPk (mixed $keys)

- mixed $keys: primary keys

findBySql (line 628)

Find records using full SQL, returns corresponding record object.

The names of the column retrieved must be defined in your Active Record class.

- return: null if no result is returned.
- access: public

TActiveRecord, findBySql (string $sql, [array $parameters = array()])

- array $parameters
- string $sql: select SQL

finder (line 357)

Returns the instance of a active record finder for a particular class.

The finder objects are static instances for each ActiveRecord class. This means that event handlers bound to these finder instances are class wide. Create a new instance of the ActiveRecord class if you wish to bound the event handlers to object instance.

- return: active record finder instance.
- static:
- access: public

TActiveRecord finder ([string $className = __CLASS__])

- string $className: active record class name.

getActiveDbConnection (line 293)

- static:
- access: public

void getActiveDbConnection ()
getColumnValue (line 913)

Retrieves the column value according to column name.

This method is used internally.

- return: the corresponding column value
- access: public
- since: 3.1.1

mixed getColumnValue (string $columnName)

- string $columnName: the column name (as defined in database schema)

getDbConnection (line 305)

Gets the current Db connection, the connection object is obtained from the TActiveRecordManager if connection is currently null.

- return: current db connection for this object.
- access: public

TDbConnection getDbConnection ()
getRecordCriteria (line 829)

Create a new TSqlCriteria object from a string $criteria. The $args are additional parameters and are used in place of the $parameters if $parameters is not an array and $args is an arrary.

- return: criteria object.
- access: protected

TSqlCriteria getRecordCriteria (string|TSqlCriteria $criteria, mixed $parameters, [array $args = array()])

- string|TSqlCriteria $criteria: sql criteria
- mixed $parameters: parameters passed by the user.
- array $args: additional parameters obtained from function_get_args().

getRecordGateway (line 381)

- return: record table gateway.
- static:
- access: public

TActiveRecordGateway getRecordGateway ()
getRecordManager (line 373)

Gets the record manager for this object, the default is to call TActiveRecordManager::getInstance().

- return: default active record manager.
- static:
- access: public

TActiveRecordManager getRecordManager ()
getRecordRelation (line 941)

- return: relation definition for the specified property
- access: public
- since: 3.1.2

array getRecordRelation (string $property)

- string $property: relation property name

getRecordRelations (line 952)

- return: all relation definitions declared in the AR class
- access: public
- since: 3.1.2

array getRecordRelations ()
getRelationHandler (line 691)

Returns the active record relationship handler for $RELATION with key value equal to the $property value.

- return: null if the context or the handler doesn't exist
- access: protected

TActiveRecordRelation, getRelationHandler (string $name, [array $args = array()])

- string $name: relationship/property name corresponding to keys in $RELATION array.
- array $args: method call arguments.

hasRecordRelation (line 962)

- return: whether a relation is declared for the specified AR property
- access: public
- since: 3.1.2

boolean hasRecordRelation (string $property)

- string $property: AR property name

onCreateCommand (line 854)

Raised when a command is prepared and parameter binding is completed.

The parameter object is TDataGatewayEventParameter of which the TDataGatewayEventParameter::getCommand property can be inspected to obtain the sql query to be executed.

Note well that the finder objects obtained from ActiveRecord::finder() method are static objects. This means that the event handlers are bound to a static finder object and not to each distinct active record object.

- access: public

void onCreateCommand (TDataGatewayEventParameter $param)

- TDataGatewayEventParameter $param

onDelete (line 891)

Raised before the record attempt to delete its data from the database.

To prevent the delete operation, set the TActiveRecordChangeEventParameter::IsValid parameter to false.

- access: public

void onDelete (TActiveRecordChangeEventParameter $param)

- TActiveRecordChangeEventParameter $param: event parameter to be passed to the event handlers

onExecuteCommand (line 871)

Raised when a command is executed and the result from the database was returned.

The parameter object is TDataGatewayResultEventParameter of which the TDataGatewayEventParameter::getResult property contains the data return from the database. The data returned can be changed by setting the TDataGatewayEventParameter::setResult property.

Note well that the finder objects obtained from ActiveRecord::finder() method are static objects. This means that the event handlers are bound to a static finder object and not to each distinct active record object.

- access: public

void onExecuteCommand (TDataGatewayResultEventParameter $param)

- TDataGatewayResultEventParameter $param

onInsert (line 881)

Raised before the record attempt to insert its data into the database.

To prevent the insert operation, set the TActiveRecordChangeEventParameter::IsValid parameter to false.

- access: public

void onInsert (TActiveRecordChangeEventParameter $param)

- TActiveRecordChangeEventParameter $param: event parameter to be passed to the event handlers

onUpdate (line 901)

Raised before the record attempt to update its data in the database.

To prevent the update operation, set the TActiveRecordChangeEventParameter::IsValid parameter to false.

- access: public

void onUpdate (TActiveRecordChangeEventParameter $param)

- TActiveRecordChangeEventParameter $param: event parameter to be passed to the event handlers

populateObject (line 497)

Populates a new record with the query result.

This is a wrapper of createRecord.

- return: object record, null if data is empty.
- access: protected

TActiveRecord populateObject (array $data)

- array $data: name value pair of record data

populateObjects (line 507)

- return: the AR objects populated by the query result
- access: protected
- since: 3.1.2

array populateObjects (TDbDataReader $reader)

- TDbDataReader $reader: data reader

save (line 390)

Saves the current record to the database, insert or update is automatically determined.

- return: true if record was saved successfully, false otherwise.
- access: public

boolean save ()
setColumnValue (line 928)

Sets the column value according to column name.

This method is used internally.

- access: public
- since: 3.1.1

void setColumnValue (string $columnName, mixed $value)

- string $columnName: the column name (as defined in database schema)
- mixed $value: the corresponding column value

setDbConnection (line 315)

- access: public

void setDbConnection (TDbConnection $connection)

- TDbConnection $connection: db connection object for this record.

__call (line 794)

Dynamic find method using parts of method name as search criteria.

Method name starting with "findBy" only returns 1 record. Method name starting with "findAllBy" returns 0 or more records. Method name starting with "deleteBy" deletes records by the trail criteria. The condition is taken as part of the method name after "findBy", "findAllBy" or "deleteBy".

The following are equivalent:

     $finder->findByName($name)
     $finder->find('Name = ?', $name);

     $finder->findByUsernameAndPassword($name,$pass); // OR may be used
      $finder->findBy_Username_And_Password($name,$pass); // _OR_ may be used
      $finder->find('Username = ? AND Password = ?', $name, $pass);

     $finder->findAllByAge($age);
     $finder->findAll('Age = ?', $age);

     $finder->deleteAll('Name = ?', $name);
     $finder->deleteByName($name);

- return: single record if method name starts with "findBy", 0 or more records if method name starts with "findAllBy"
- access: public

mixed __call (mixed $method, mixed $args)
__get (line 223)

Magic method for reading properties.

This method is overriden to provide read access to the foreign objects via the key names declared in the RELATIONS array.

- return: property value.
- access: public
- since: 3.1.2

mixed __get (string $name)

- string $name: property name

Redefinition of:

TComponent::__get()
  Returns a property value or an event handler list by property or event name.

__set (line 241)

Magic method for writing properties.

This method is overriden to provide write access to the foreign objects via the key names declared in the RELATIONS array.

- access: public
- since: 3.1.2

void __set (string $name, mixed $value)

- string $name: property name
- mixed $value: property value.

Redefinition of:

TComponent::__set()
  Sets value of a component property.

__sleep (line 183)

Prevent __call() method creating __sleep() when serializing.

- access: public

void __sleep ()
__wakeup (line 192)

Prevent __call() method creating __wakeup() when unserializing.

- access: public

void __wakeup ()

#### Inherited Methods

Inherited From TComponent

> TComponent::addParsedObject()
> TComponent::attachEventHandler()
> TComponent::canGetProperty()
> TComponent::canSetProperty()
> TComponent::createdOnTemplate()
> TComponent::detachEventHandler()
> TComponent::evaluateExpression()
> TComponent::evaluateStatements()
> TComponent::getEventHandlers()
> TComponent::getSubProperty()
> TComponent::hasEvent()
> TComponent::hasEventHandler()
> TComponent::hasProperty()
> TComponent::raiseEvent()
> TComponent::setSubProperty()
> TComponent::__get()
> TComponent::__set()

Class Constants
BELONGS_TO = 'BELONGS_TO' (line 139)
HAS_MANY = 'HAS_MANY' (line 141)
HAS_ONE = 'HAS_ONE' (line 140)
MANY_TO_MANY = 'MANY_TO_MANY' (line 142)
STATE_DELETED = 2 (line 146)
STATE_LOADED = 1 (line 145)
STATE_NEW = 0 (line 144)

Documentation generated on Mon, 21 Apr 2008 11:29:38 -0400 by phpDocumentor 1.3.0RC4