Proyectos de Subversion Moodle

<?php

/**

 * Active Record implementation. Superset of Zend Framework's.

 *

 * This file is part of ADOdb, a Database Abstraction Layer library for PHP.

 *

 * @package ADOdb

 * @link https://adodb.org Project's web site and documentation

 * @link https://github.com/ADOdb/ADOdb Source code and issue tracker

 *

 * The ADOdb Library is dual-licensed, released under both the BSD 3-Clause

 * and the GNU Lesser General Public Licence (LGPL) v2.1 or, at your option,

 * any later version. This means you can use it in proprietary products.

 * See the LICENSE.md file distributed with this source code for details.

 * @license BSD-3-Clause

 * @license LGPL-2.1-or-later

 *

 * @copyright 2000-2013 John Lim

 * @copyright 2014 Damien Regad, Mark Newnham and the ADOdb community

 */

include_once(ADODB_DIR.'/adodb-lib.inc.php');

global $_ADODB_ACTIVE_DBS;

global $ADODB_ACTIVE_CACHESECS; // set to true to enable caching of metadata such as field info

global $ACTIVE_RECORD_SAFETY; // set to false to disable safety checks

global $ADODB_ACTIVE_DEFVALS; // use default values of table definition when creating new active record.

// array of ADODB_Active_DB's, indexed by ADODB_Active_Record->_dbat

$_ADODB_ACTIVE_DBS = array();

$ACTIVE_RECORD_SAFETY = true;

$ADODB_ACTIVE_DEFVALS = false;

$ADODB_ACTIVE_CACHESECS = 0;

class ADODB_Active_DB {

	var $db; // ADOConnection

	var $tables; // assoc array of ADODB_Active_Table objects, indexed by tablename

}

class ADODB_Active_Table {

	var $name; // table name

	var $flds; // assoc array of adofieldobjs, indexed by fieldname

	var $keys; // assoc array of primary keys, indexed by fieldname

	var $_created; // only used when stored as a cached file

	var $_belongsTo = array();

	var $_hasMany = array();

}

// $db = database connection

// $index = name of index - can be associative, for an example see

//    PHPLens Issue No: 17790

// returns index into $_ADODB_ACTIVE_DBS

function ADODB_SetDatabaseAdapter(&$db, $index=false)

{

	global $_ADODB_ACTIVE_DBS;

	foreach($_ADODB_ACTIVE_DBS as $k => $d) {

		if($d->db === $db) {

			return $k;

		}

	}

	$obj = new ADODB_Active_DB();

	$obj->db = $db;

	$obj->tables = array();

	if ($index == false) {

		$index = sizeof($_ADODB_ACTIVE_DBS);

	}

	$_ADODB_ACTIVE_DBS[$index] = $obj;

	return sizeof($_ADODB_ACTIVE_DBS)-1;

}

class ADODB_Active_Record {

	static $_changeNames = true; // dynamically pluralize table names

	/** @var bool|string Allows override of global $ADODB_QUOTE_FIELDNAMES */

	public $_quoteNames;

	static $_foreignSuffix = '_id'; //

	var $_dbat; // associative index pointing to ADODB_Active_DB eg. $ADODB_Active_DBS[_dbat]

	var $_table; // tablename, if set in class definition then use it as table name

	var $_tableat; // associative index pointing to ADODB_Active_Table, eg $ADODB_Active_DBS[_dbat]->tables[$this->_tableat]

	var $_where; // where clause set in Load()

	var $_saved = false; // indicates whether data is already inserted.

	var $_lasterr = false; // last error message

	var $_original = false; // the original values loaded or inserted, refreshed on update

	var $foreignName; // CFR: class name when in a relationship

	var $lockMode = ' for update '; // you might want to change to

	static function UseDefaultValues($bool=null)

	{

	global $ADODB_ACTIVE_DEFVALS;

		if (isset($bool)) {

			$ADODB_ACTIVE_DEFVALS = $bool;

		}

		return $ADODB_ACTIVE_DEFVALS;

	}

	// should be static

	static function SetDatabaseAdapter(&$db, $index=false)

	{

		return ADODB_SetDatabaseAdapter($db, $index);

	}

	public function __set($name, $value)

	{

		$name = str_replace(' ', '_', $name);

		$this->$name = $value;

	}

	// php5 constructor

	function __construct($table = false, $pkeyarr=false, $db=false)

	{

		global $_ADODB_ACTIVE_DBS, $ADODB_QUOTE_FIELDNAMES;

		// Set the local override for field quoting, only if not defined yet

		if (!isset($this->_quoteNames)) {

			$this->_quoteNames = $ADODB_QUOTE_FIELDNAMES;

		}

		if ($db == false && is_object($pkeyarr)) {

			$db = $pkeyarr;

			$pkeyarr = false;

		}

		if (!$table) {

			if (!empty($this->_table)) {

				$table = $this->_table;

			}

			else $table = $this->_pluralize(get_class($this));

		}

		$this->foreignName = strtolower(get_class($this)); // CFR: default foreign name

		if ($db) {

			$this->_dbat = ADODB_Active_Record::SetDatabaseAdapter($db);

		} else if (!isset($this->_dbat)) {

			if (sizeof($_ADODB_ACTIVE_DBS) == 0) {

				$this->Error(

					"No database connection set; use ADOdb_Active_Record::SetDatabaseAdapter(\$db)",

					'ADODB_Active_Record::__constructor'

				);

			}

			end($_ADODB_ACTIVE_DBS);

			$this->_dbat = key($_ADODB_ACTIVE_DBS);

		}

		$this->_table = $table;

		$this->_tableat = $table; # reserved for setting the assoc value to a non-table name, eg. the sql string in future

		$this->UpdateActiveTable($pkeyarr);

	}

	function __wakeup()

	{

  		$class = get_class($this);

  		new $class;

	}

	function _pluralize($table)

	{

		if (!ADODB_Active_Record::$_changeNames) {

			return $table;

		}

		$ut = strtoupper($table);

		$len = strlen($table);

		$lastc = $ut[$len-1];

		$lastc2 = substr($ut,$len-2);

		switch ($lastc) {

		case 'S':

			return $table.'es';

		case 'Y':

			return substr($table,0,$len-1).'ies';

		case 'X':

			return $table.'es';

		case 'H':

			if ($lastc2 == 'CH' || $lastc2 == 'SH') {

				return $table.'es';

			}

		default:

			return $table.'s';

		}

	}

	// CFR Lamest singular inflector ever - @todo Make it real!

	// Note: There is an assumption here...and it is that the argument's length >= 4

	function _singularize($tables)

	{

		if (!ADODB_Active_Record::$_changeNames) {

			return $table;

		}

		$ut = strtoupper($tables);

		$len = strlen($tables);

		if($ut[$len-1] != 'S') {

			return $tables; // I know...forget oxen

		}

		if($ut[$len-2] != 'E') {

			return substr($tables, 0, $len-1);

		}

		switch($ut[$len-3]) {

			case 'S':

			case 'X':

				return substr($tables, 0, $len-2);

			case 'I':

				return substr($tables, 0, $len-3) . 'y';

			case 'H';

				if($ut[$len-4] == 'C' || $ut[$len-4] == 'S') {

					return substr($tables, 0, $len-2);

				}

			default:

				return substr($tables, 0, $len-1); // ?

		}

	}

	function hasMany($foreignRef, $foreignKey = false, $foreignClass = 'ADODB_Active_Record')

	{

		$ar = new $foreignClass($foreignRef);

		$ar->foreignName = $foreignRef;

		$ar->UpdateActiveTable();

		$ar->foreignKey = ($foreignKey) ? $foreignKey : $foreignRef.ADODB_Active_Record::$_foreignSuffix;

		$table =& $this->TableInfo();

		$table->_hasMany[$foreignRef] = $ar;

	#	$this->$foreignRef = $this->_hasMany[$foreignRef]; // WATCHME Removed assignment by ref. to please __get()

	}

	// use when you don't want ADOdb to auto-pluralize tablename

	static function TableHasMany($table, $foreignRef, $foreignKey = false, $foreignClass = 'ADODB_Active_Record')

	{

		$ar = new ADODB_Active_Record($table);

		$ar->hasMany($foreignRef, $foreignKey, $foreignClass);

	}

	// use when you don't want ADOdb to auto-pluralize tablename

	static function TableKeyHasMany($table, $tablePKey, $foreignRef, $foreignKey = false, $foreignClass = 'ADODB_Active_Record')

	{

		if (!is_array($tablePKey)) {

			$tablePKey = array($tablePKey);

		}

		$ar = new ADODB_Active_Record($table,$tablePKey);

		$ar->hasMany($foreignRef, $foreignKey, $foreignClass);

	}

	// use when you want ADOdb to auto-pluralize tablename for you. Note that the class must already be defined.

	// e.g. class Person will generate relationship for table Persons

	static function ClassHasMany($parentclass, $foreignRef, $foreignKey = false, $foreignClass = 'ADODB_Active_Record')

	{

		$ar = new $parentclass();

		$ar->hasMany($foreignRef, $foreignKey, $foreignClass);

	}

	function belongsTo($foreignRef,$foreignKey=false, $parentKey='', $parentClass = 'ADODB_Active_Record')

	{

		global $inflector;

		$ar = new $parentClass($this->_pluralize($foreignRef));

		$ar->foreignName = $foreignRef;

		$ar->parentKey = $parentKey;

		$ar->UpdateActiveTable();

		$ar->foreignKey = ($foreignKey) ? $foreignKey : $foreignRef.ADODB_Active_Record::$_foreignSuffix;

		$table =& $this->TableInfo();

		$table->_belongsTo[$foreignRef] = $ar;

	#	$this->$foreignRef = $this->_belongsTo[$foreignRef];

	}

	static function ClassBelongsTo($class, $foreignRef, $foreignKey=false, $parentKey='', $parentClass = 'ADODB_Active_Record')

	{

		$ar = new $class();

		$ar->belongsTo($foreignRef, $foreignKey, $parentKey, $parentClass);

	}

	static function TableBelongsTo($table, $foreignRef, $foreignKey=false, $parentKey='', $parentClass = 'ADODB_Active_Record')

	{

		$ar = new ADODB_Active_Record($table);

		$ar->belongsTo($foreignRef, $foreignKey, $parentKey, $parentClass);

	}

	static function TableKeyBelongsTo($table, $tablePKey, $foreignRef, $foreignKey=false, $parentKey='', $parentClass = 'ADODB_Active_Record')

	{

		if (!is_array($tablePKey)) {

			$tablePKey = array($tablePKey);

		}

		$ar = new ADODB_Active_Record($table, $tablePKey);

		$ar->belongsTo($foreignRef, $foreignKey, $parentKey, $parentClass);

	}

	/**

	 * __get Access properties - used for lazy loading

	 *

	 * @param mixed $name

	 * @access protected

	 * @return mixed

	 */

	 function __get($name)

	{

		return $this->LoadRelations($name, '', -1, -1);

	}

	/**

	 * @param string $name

	 * @param string $whereOrderBy : eg. ' AND field1 = value ORDER BY field2'

	 * @param offset

	 * @param limit

	 * @return mixed

	 */

	function LoadRelations($name, $whereOrderBy='', $offset=-1,$limit=-1)

	{

		$extras = array();

		$table = $this->TableInfo();

		if ($limit >= 0) {

			$extras['limit'] = $limit;

		}

		if ($offset >= 0) {

			$extras['offset'] = $offset;

		}

		if (strlen($whereOrderBy)) {

			if (!preg_match('/^[ \n\r]*AND/i', $whereOrderBy)) {

				if (!preg_match('/^[ \n\r]*ORDER[ \n\r]/i', $whereOrderBy)) {

					$whereOrderBy = 'AND ' . $whereOrderBy;

				}

			}

		}

		if(!empty($table->_belongsTo[$name])) {

			$obj = $table->_belongsTo[$name];

			$columnName = $obj->foreignKey;

			if(empty($this->$columnName)) {

				$this->$name = null;

			}

			else {

				if ($obj->parentKey) {

					$key = $obj->parentKey;

				}

				else {

					$key = reset($table->keys);

				}

				$arrayOfOne = $obj->Find($key.'='.$this->$columnName.' '.$whereOrderBy,false,false,$extras);

				if ($arrayOfOne) {

					$this->$name = $arrayOfOne[0];

					return $arrayOfOne[0];

				}

			}

		}

		if(!empty($table->_hasMany[$name])) {

			$obj = $table->_hasMany[$name];

			$key = reset($table->keys);

			$id = @$this->$key;

			if (!is_numeric($id)) {

				$db = $this->DB();

				$id = $db->qstr($id);

			}

			$objs = $obj->Find($obj->foreignKey.'='.$id. ' '.$whereOrderBy,false,false,$extras);

			if (!$objs) {

				$objs = array();

			}

			$this->$name = $objs;

			return $objs;

		}

		return array();

	}

	//////////////////////////////////

	// update metadata

	function UpdateActiveTable($pkeys=false,$forceUpdate=false)

	{

	global $_ADODB_ACTIVE_DBS , $ADODB_CACHE_DIR, $ADODB_ACTIVE_CACHESECS;

	global $ADODB_ACTIVE_DEFVALS,$ADODB_FETCH_MODE;

		$activedb = $_ADODB_ACTIVE_DBS[$this->_dbat];

		$table = $this->_table;

		$tables = $activedb->tables;

		$tableat = $this->_tableat;

		if (!$forceUpdate && !empty($tables[$tableat])) {

			$acttab = $tables[$tableat];

			foreach($acttab->flds as $name => $fld) {

				if ($ADODB_ACTIVE_DEFVALS && isset($fld->default_value)) {

					$this->$name = $fld->default_value;

				}

				else {

					$this->$name = null;

				}

			}

			return;

		}

		$db = $activedb->db;

		$fname = $ADODB_CACHE_DIR . '/adodb_' . $db->databaseType . '_active_'. $table . '.cache';

		if (!$forceUpdate && $ADODB_ACTIVE_CACHESECS && $ADODB_CACHE_DIR && file_exists($fname)) {

			$fp = fopen($fname,'r');

			@flock($fp, LOCK_SH);

			$acttab = unserialize(fread($fp,100000));

			fclose($fp);

			if ($acttab->_created + $ADODB_ACTIVE_CACHESECS - (abs(rand()) % 16) > time()) {

				// abs(rand()) randomizes deletion, reducing contention to delete/refresh file

				// ideally, you should cache at least 32 secs

				foreach($acttab->flds as $name => $fld) {

					if ($ADODB_ACTIVE_DEFVALS && isset($fld->default_value)) {

						$this->$name = $fld->default_value;

					}

					else {

						$this->$name = null;

					}

				}

				$activedb->tables[$table] = $acttab;

				//if ($db->debug) ADOConnection::outp("Reading cached active record file: $fname");

			  	return;

			} else if ($db->debug) {

				ADOConnection::outp("Refreshing cached active record file: $fname");

			}

		}

		$activetab = new ADODB_Active_Table();

		$activetab->name = $table;

		$save = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_ASSOC;

		if ($db->fetchMode !== false) {

			$savem = $db->SetFetchMode(false);

		}

		$cols = $db->MetaColumns($table);

		if (isset($savem)) {

			$db->SetFetchMode($savem);

		}

		$ADODB_FETCH_MODE = $save;

		if (!$cols) {

			$this->Error("Invalid table name: $table",'UpdateActiveTable');

			return false;

		}

		$fld = reset($cols);

		if (!$pkeys) {

			if (isset($fld->primary_key)) {

				$pkeys = array();

				foreach($cols as $name => $fld) {

					if (!empty($fld->primary_key)) {

						$pkeys[] = $name;

					}

				}

			} else

				$pkeys = $this->GetPrimaryKeys($db, $table);

		}

		if (empty($pkeys)) {

			$this->Error("No primary key found for table $table",'UpdateActiveTable');

			return false;

		}

		$attr = array();

		$keys = array();

		switch (ADODB_ASSOC_CASE) {

		case ADODB_ASSOC_CASE_LOWER:

			foreach($cols as $name => $fldobj) {

				$name = strtolower($name);

				if ($ADODB_ACTIVE_DEFVALS && isset($fldobj->default_value)) {

					$this->$name = $fldobj->default_value;

				}

				else {

					$this->$name = null;

				}

				$attr[$name] = $fldobj;

			}

			foreach($pkeys as $k => $name) {

				$keys[strtolower($name)] = strtolower($name);

			}

			break;

		case ADODB_ASSOC_CASE_UPPER:

			foreach($cols as $name => $fldobj) {

				$name = strtoupper($name);

				if ($ADODB_ACTIVE_DEFVALS && isset($fldobj->default_value)) {

					$this->$name = $fldobj->default_value;

				}

				else {

					$this->$name = null;

				}

				$attr[$name] = $fldobj;

			}

			foreach($pkeys as $k => $name) {

				$keys[strtoupper($name)] = strtoupper($name);

			}

			break;

		default:

			foreach($cols as $fldobj) {

				$name = $fldobj->name;

				if ($ADODB_ACTIVE_DEFVALS && isset($fldobj->default_value)) {

					$this->$name = $fldobj->default_value;

				}

				else {

					$this->$name = null;

				}

				$attr[$name] = $fldobj;

			}

			foreach($pkeys as $k => $name) {

				$keys[$name] = $cols[strtoupper($name)]->name;

			}

			break;

		}

		$activetab->keys = $keys;

		$activetab->flds = $attr;

		if ($ADODB_ACTIVE_CACHESECS && $ADODB_CACHE_DIR) {

			$activetab->_created = time();

			$s = serialize($activetab);

			if (!function_exists('adodb_write_file')) {

				include_once(ADODB_DIR.'/adodb-csvlib.inc.php');

			}

			adodb_write_file($fname,$s);

		}

		if (isset($activedb->tables[$table])) {

			$oldtab = $activedb->tables[$table];

			if ($oldtab) {

				$activetab->_belongsTo = $oldtab->_belongsTo;

				$activetab->_hasMany = $oldtab->_hasMany;

			}

		}

		$activedb->tables[$table] = $activetab;

	}

	function GetPrimaryKeys(&$db, $table)

	{

		return $db->MetaPrimaryKeys($table);

	}

	// error handler for both PHP4+5.

	function Error($err,$fn)

	{

	global $_ADODB_ACTIVE_DBS;

		$fn = get_class($this).'::'.$fn;

		$this->_lasterr = $fn.': '.$err;

		if ($this->_dbat < 0) {

			$db = false;

		}

		else {

			$activedb = $_ADODB_ACTIVE_DBS[$this->_dbat];

			$db = $activedb->db;

		}

		if (function_exists('adodb_throw')) {

			if (!$db) {

				adodb_throw('ADOdb_Active_Record', $fn, -1, $err, 0, 0, false);

			}

			else {

				adodb_throw($db->databaseType, $fn, -1, $err, 0, 0, $db);

			}

		} else {

			if (!$db || $db->debug) {

				ADOConnection::outp($this->_lasterr);

			}

		}

	}

	// return last error message

	function ErrorMsg()

	{

		if (!function_exists('adodb_throw')) {

			if ($this->_dbat < 0) {

				$db = false;

			}

			else {

				$db = $this->DB();

			}

			// last error could be database error too

			if ($db && $db->ErrorMsg()) {

				return $db->ErrorMsg();

			}

		}

		return $this->_lasterr;

	}

	function ErrorNo()

	{

		if ($this->_dbat < 0) {

			return -9999; // no database connection...

		}

		$db = $this->DB();

		return (int) $db->ErrorNo();

	}

	// retrieve ADOConnection from _ADODB_Active_DBs

	function DB()

	{

	global $_ADODB_ACTIVE_DBS;

		if ($this->_dbat < 0) {

			$false = false;

			$this->Error("No database connection set: use ADOdb_Active_Record::SetDatabaseAdaptor(\$db)", "DB");

			return $false;

		}

		$activedb = $_ADODB_ACTIVE_DBS[$this->_dbat];

		$db = $activedb->db;

		return $db;

	}

	// retrieve ADODB_Active_Table

	function &TableInfo()

	{

	global $_ADODB_ACTIVE_DBS;

		$activedb = $_ADODB_ACTIVE_DBS[$this->_dbat];

		$table = $activedb->tables[$this->_tableat];

		return $table;

	}

	// I have an ON INSERT trigger on a table that sets other columns in the table.

	// So, I find that for myTable, I want to reload an active record after saving it. -- Malcolm Cook

	function Reload()

	{

		$db = $this->DB();

		if (!$db) {

			return false;

		}

		$table = $this->TableInfo();

		$where = $this->GenWhere($db, $table);

		return($this->Load($where));

	}

	// set a numeric array (using natural table field ordering) as object properties

	function Set(&$row)

	{

	global $ACTIVE_RECORD_SAFETY;

		$db = $this->DB();

		if (!$row) {

			$this->_saved = false;

			return false;

		}

		$this->_saved = true;

		$table = $this->TableInfo();

		if ($ACTIVE_RECORD_SAFETY && sizeof($table->flds) != sizeof($row)) {

			# <AP>

			$bad_size = TRUE;

			if (sizeof($row) == 2 * sizeof($table->flds)) {

				// Only keep string keys

				$keys = array_filter(array_keys($row), 'is_string');

				if (sizeof($keys) == sizeof($table->flds)) {

					$bad_size = FALSE;

				}

			}

			if ($bad_size) {

			$this->Error("Table structure of $this->_table has changed","Load");

			return false;

		}

			# </AP>

		}

		else

			$keys = array_keys($row);

		# <AP>

		reset($keys);

		$this->_original = array();

		foreach($table->flds as $name=>$fld) {

			$value = $row[current($keys)];

			$this->$name = $value;

			$this->_original[] = $value;

			next($keys);

		}

		# </AP>

		return true;

	}

	// get last inserted id for INSERT

	function LastInsertID(&$db,$fieldname)

	{

		if ($db->hasInsertID) {

			$val = $db->Insert_ID($this->_table,$fieldname);

		}

		else {

			$val = false;

		}

		if (is_null($val) || $val === false)

		{

			$SQL = sprintf("SELECT MAX(%s) FROM %s",

						   $this->nameQuoter($db,$fieldname),

						   $this->nameQuoter($db,$this->_table)

						   );

			// this might not work reliably in multi-user environment

			return $db->GetOne($SQL);

		}

		return $val;

	}

	// quote data in where clause

	function doquote(&$db, $val,$t)

	{

		switch($t) {

		case 'L':

			if (strpos($db->databaseType,'postgres') !== false) {

				return $db->qstr($val);

			}

		case 'D':

		case 'T':

			if (empty($val)) {

				return 'null';

			}

		case 'B':

		case 'N':

		case 'C':

		case 'X':

			if (is_null($val)) {

				return 'null';

			}

			if (strlen($val)>0 &&

				(strncmp($val,"'",1) != 0 || substr($val,strlen($val)-1,1) != "'")

			) {

				return $db->qstr($val);

				break;

			}

		default:

			return $val;

			break;

		}

	}

	// generate where clause for an UPDATE/SELECT

	function GenWhere(&$db, &$table)

	{

		$keys = $table->keys;

		$parr = array();

		foreach($keys as $k) {

			$f = $table->flds[$k];

			if ($f) {

				$columnName = $this->nameQuoter($db,$k);

				$parr[] = $columnName.' = '.$this->doquote($db,$this->$k,$db->MetaType($f->type));

			}

		}

		return implode(' AND ', $parr);

	}

	function _QName($n,$db=false)

	{

		if (!ADODB_Active_Record::$_quoteNames) {

			return $n;

		}

		if (!$db) {

			$db = $this->DB();

			if (!$db) {

				return false;

			}

		}

		return $db->nameQuote.$n.$db->nameQuote;

	}

	//------------------------------------------------------------ Public functions below

	function Load($where=null,$bindarr=false, $lock = false)

	{

		global $ADODB_FETCH_MODE;

		$db = $this->DB();

		if (!$db) {

			return false;

		}

		$this->_where = $where;

		$save = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		if ($db->fetchMode !== false) {

			$savem = $db->SetFetchMode(false);

		}

		$qry = sprintf("SELECT * FROM %s",

					   $this->nameQuoter($db,$this->_table)

					   );

		if($where) {

			$qry .= ' WHERE '.$where;

		}

		if ($lock) {

			$qry .= $this->lockMode;

		}

		$row = $db->GetRow($qry,$bindarr);

		if (isset($savem)) {

			$db->SetFetchMode($savem);

		}

		$ADODB_FETCH_MODE = $save;

		return $this->Set($row);

	}

	function LoadLocked($where=null, $bindarr=false)

	{

		$this->Load($where,$bindarr,true);

	}

	# useful for multiple record inserts

	# see PHPLens Issue No: 17795

	function Reset()

	{

		$this->_where=null;

		$this->_saved = false;

		$this->_lasterr = false;

		$this->_original = false;

		$vars=get_object_vars($this);

		foreach($vars as $k=>$v){

			if(substr($k,0,1)!=='_'){

				$this->{$k}=null;

			}

		}

		$this->foreignName=strtolower(get_class($this));

		return true;

	}

	// false on error

	function Save()

	{

		if ($this->_saved) {

			$ok = $this->Update();

		}

		else {

			$ok = $this->Insert();

		}

		return $ok;

	}

	// false on error

	function Insert()

	{

		$db = $this->DB();

		if (!$db) {

			return false;

		}

		$cnt = 0;

		$table = $this->TableInfo();

		$valarr = array();

		$names = array();

		$valstr = array();

		foreach($table->flds as $name=>$fld) {

			$val = $this->$name;

			if(!is_array($val) || !is_null($val) || !array_key_exists($name, $table->keys)) {

				$valarr[] = $val;

				$names[] = $this->nameQuoter($db,$name);

				$valstr[] = $db->Param($cnt);

				$cnt += 1;

			}

		}

		if (empty($names)){

			foreach($table->flds as $name=>$fld) {

				$valarr[] = null;

				$names[] = $this->nameQuoter($db,$name);

				$valstr[] = $db->Param($cnt);

				$cnt += 1;

			}

		}

		$tableName = $this->nameQuoter($db,$this->_table);

		$sql = sprintf('INSERT INTO %s (%s) VALUES (%s)',

					   $tableName,

					   implode(',',$names),

					   implode(',',$valstr)

					   );

		$ok = $db->Execute($sql,$valarr);

		if ($ok) {

			$this->_saved = true;

			$autoinc = false;

			foreach($table->keys as $k) {

				if (is_null($this->$k)) {

					$autoinc = true;

					break;

				}

			}

			if ($autoinc && sizeof($table->keys) == 1) {

				$k = reset($table->keys);

				$this->$k = $this->LastInsertID($db,$k);

			}

		}

		$this->_original = $valarr;

		return !empty($ok);

	}

	function Delete()

	{

		$db = $this->DB();

		if (!$db) {

			return false;

		}

		$table = $this->TableInfo();

		$where = $this->GenWhere($db,$table);

		$tableName = $this->nameQuoter($db,$this->_table);

		$sql = sprintf('DELETE FROM %s WHERE %s',

					   $tableName,

					   $where

					   );

		$ok = $db->Execute($sql);

		return $ok ? true : false;

	}

	// returns an array of active record objects

	function Find($whereOrderBy,$bindarr=false,$pkeysArr=false,$extra=array())

	{

		$db = $this->DB();

		if (!$db || empty($this->_table)) {

			return false;

		}

		$arr = $db->GetActiveRecordsClass(get_class($this),$this->_table, $whereOrderBy,$bindarr,$pkeysArr,$extra);

		return $arr;

	}

	// returns 0 on error, 1 on update, 2 on insert

	function Replace()

	{

		$db = $this->DB();

		if (!$db) {

			return false;

		}

		$table = $this->TableInfo();

		$pkey = $table->keys;

		foreach($table->flds as $name=>$fld) {

			$val = $this->$name;

			/*

			if (is_null($val)) {

				if (isset($fld->not_null) && $fld->not_null) {

					if (isset($fld->default_value) && strlen($fld->default_value)) {

						continue;

					}

					else {

						$this->Error("Cannot update null into $name","Replace");

						return false;

					}

				}

			}*/

			if (is_null($val) && !empty($fld->auto_increment)) {

				continue;

			}

			if (is_array($val)) {

				continue;

			}

			$t = $db->MetaType($fld->type);

			$arr[$name] = $this->doquote($db,$val,$t);

			$valarr[] = $val;

		}

		if (!is_array($pkey)) {

			$pkey = array($pkey);

		}

		switch (ADODB_ASSOC_CASE) {

			case ADODB_ASSOC_CASE_LOWER:

				foreach ($pkey as $k => $v) {

					$pkey[$k] = strtolower($v);

				}

				break;

			case ADODB_ASSOC_CASE_UPPER:

				foreach ($pkey as $k => $v) {

					$pkey[$k] = strtoupper($v);

				}

				break;

		}