diff --git a/core/dbsearch.class.php b/core/dbsearch.class.php
index 6ee33e931..8e57cc811 100644
--- a/core/dbsearch.class.php
+++ b/core/dbsearch.class.php
@@ -1,843 +1,875 @@
-<?php
-// Copyright (C) 2015-2017 Combodo SARL
-//
-//   This file is part of iTop.
-//
-//   iTop is free software; you can redistribute it and/or modify	
-//   it under the terms of the GNU Affero General Public License as published by
-//   the Free Software Foundation, either version 3 of the License, or
-//   (at your option) any later version.
-//
-//   iTop is distributed in the hope that it will be useful,
-//   but WITHOUT ANY WARRANTY; without even the implied warranty of
-//   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-//   GNU Affero General Public License for more details.
-//
-//   You should have received a copy of the GNU Affero General Public License
-//   along with iTop. If not, see <http://www.gnu.org/licenses/>
-
-
-require_once('dbobjectsearch.class.php');
-require_once('dbunionsearch.class.php');
-
-/**
- * An object search
- * 
- * Note: in the ancient times of iTop, a search was named after DBObjectSearch.
- *  When the UNION has been introduced, it has been decided to:
- *  - declare a hierarchy of search classes, with two leafs :
- *    - one class to cope with a single query (A JOIN B... WHERE...)
- *    - and the other to cope with several queries (query1 UNION query2)
- *  - in order to preserve forward/backward compatibility of the existing modules 
- *    - keep the name of DBObjectSearch even if it a little bit confusing
- *    - do not provide a type-hint for function parameters defined in the modules
- *    - leave the statements DBObjectSearch::FromOQL in the modules, though DBSearch is more relevant 
- *
- * @copyright   Copyright (C) 2015-2017 Combodo SARL
- * @license     http://opensource.org/licenses/AGPL-3.0
- */
- 
-abstract class DBSearch
-{
-	const JOIN_POINTING_TO = 0;
-	const JOIN_REFERENCED_BY = 1;
-
-	protected $m_bNoContextParameters = false;
-	protected $m_aModifierProperties = array();
-	protected $m_bArchiveMode = false;
-	protected $m_bShowObsoleteData = true;
-
-	public function __construct()
-	{
-		$this->m_bArchiveMode = utils::IsArchiveMode();
-	}
-
-	/**
-	 * Perform a deep clone (as opposed to "clone" which does copy a reference to the underlying objects)
-	 **/	 	
-	public function DeepClone()
-	{
-		return unserialize(serialize($this)); // Beware this serializes/unserializes the search and its parameters as well
-	}
-
-	abstract public function AllowAllData();
-	abstract public function IsAllDataAllowed();
-
-	public function SetArchiveMode($bEnable)
-	{
-		$this->m_bArchiveMode = $bEnable;
-	}
-	public function GetArchiveMode()
-	{
-		return $this->m_bArchiveMode;
-	}
-
-	public function SetShowObsoleteData($bShow)
-	{
-		$this->m_bShowObsoleteData = $bShow;
-	}
-	public function GetShowObsoleteData()
-	{
-		if ($this->m_bArchiveMode || $this->IsAllDataAllowed())
-		{
-			// Enable obsolete data too!
-			$bRet = true;
-		}
-		else
-		{
-			$bRet = $this->m_bShowObsoleteData;
-		}
-		return $bRet;
-	}
-
-	public function NoContextParameters() {$this->m_bNoContextParameters = true;}
-	public function HasContextParameters() {return $this->m_bNoContextParameters;}
-
-	public function SetModifierProperty($sPluginClass, $sProperty, $value)
-	{
-		$this->m_aModifierProperties[$sPluginClass][$sProperty] = $value;
-	}
-
-	public function GetModifierProperties($sPluginClass)
-	{
-		if (array_key_exists($sPluginClass, $this->m_aModifierProperties))
-		{
-			return $this->m_aModifierProperties[$sPluginClass];
-		}
-		else
-		{
-			return array();
-		}
-	}
-
-	abstract public function GetClassName($sAlias);
-	abstract public function GetClass();
-	abstract public function GetClassAlias();
-
-	/**
-	 * Change the class (only subclasses are supported as of now, because the conditions must fit the new class)
-	 * Defaults to the first selected class (most of the time it is also the first joined class	 
-	 */	 	
-	abstract public function ChangeClass($sNewClass, $sAlias = null);
-	abstract public function GetSelectedClasses();
-
-	/**
-	 * @param array $aSelectedClasses array of aliases
-	 * @throws CoreException
-	 */
-	abstract public function SetSelectedClasses($aSelectedClasses);
-
-	/**
-	 * Change any alias of the query tree
-	 *
-	 * @param $sOldName
-	 * @param $sNewName
-	 * @return bool True if the alias has been found and changed
-	 */
-	abstract public function RenameAlias($sOldName, $sNewName);
-
-	abstract public function IsAny();
-
-	public function Describe(){return 'deprecated - use ToOQL() instead';}
-	public function DescribeConditionPointTo($sExtKeyAttCode, $aPointingTo){return 'deprecated - use ToOQL() instead';}
-	public function DescribeConditionRefBy($sForeignClass, $sForeignExtKeyAttCode){return 'deprecated - use ToOQL() instead';}
-	public function DescribeConditionRelTo($aRelInfo){return 'deprecated - use ToOQL() instead';}
-	public function DescribeConditions(){return 'deprecated - use ToOQL() instead';}
-	public function __DescribeHTML(){return 'deprecated - use ToOQL() instead';}
-
-	abstract public function ResetCondition();
-	abstract public function MergeConditionExpression($oExpression);
-	abstract public function AddConditionExpression($oExpression);
-  	abstract public function AddNameCondition($sName);
-	abstract public function AddCondition($sFilterCode, $value, $sOpCode = null);
-	/**
-	 * Specify a condition on external keys or link sets
-	 * @param sAttSpec Can be either an attribute code or extkey->[sAttSpec] or linkset->[sAttSpec] and so on, recursively
-	 *                 Example: infra_list->ci_id->location_id->country	 
-	 * @param value The value to match (can be an array => IN(val1, val2...)
-	 * @return void
-	 */
-	abstract public function AddConditionAdvanced($sAttSpec, $value);
-	abstract public function AddCondition_FullText($sFullText);
-
-	/**
-	 * @param DBObjectSearch $oFilter
-	 * @param $sExtKeyAttCode
-	 * @param int $iOperatorCode
-	 * @param null $aRealiasingMap array of <old-alias> => <new-alias>, for each alias that has changed
-	 * @throws CoreException
-	 * @throws CoreWarning
-	 */
-	abstract public function AddCondition_PointingTo(DBObjectSearch $oFilter, $sExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null);
-
-	/**
-	 * @param DBObjectSearch $oFilter
-	 * @param $sForeignExtKeyAttCode
-	 * @param int $iOperatorCode
-	 * @param null $aRealiasingMap array of <old-alias> => <new-alias>, for each alias that has changed
-	 */
-	abstract public function AddCondition_ReferencedBy(DBObjectSearch $oFilter, $sForeignExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null);
-
-	abstract public function Intersect(DBSearch $oFilter);
-
-	/**
-	 * @param DBSearch $oFilter
-	 * @param integer $iDirection
-	 * @param string $sExtKeyAttCode
-	 * @param integer $iOperatorCode
-	 * @param array &$RealisasingMap  Map of aliases from the attached query, that could have been renamed by the optimization process
-	 * @return DBSearch
-	 */
-	public function Join(DBSearch $oFilter, $iDirection, $sExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null)
-	{
-		$oSourceFilter = $this->DeepClone();
-		$oRet = null;
-
-		if ($oFilter instanceof DBUnionSearch)
-		{
-			$aSearches = array();
-			foreach ($oFilter->GetSearches() as $oSearch)
-			{
-				$aSearches[] = $oSourceFilter->Join($oSearch, $iDirection, $sExtKeyAttCode, $iOperatorCode, $aRealiasingMap);
-			}
-			$oRet = new DBUnionSearch($aSearches);
-		}
-		else
-		{
-			if ($iDirection === static::JOIN_POINTING_TO)
-			{
-				$oSourceFilter->AddCondition_PointingTo($oFilter, $sExtKeyAttCode, $iOperatorCode, $aRealiasingMap);
-			}
-			else
-			{
-				if ($iOperatorCode !== TREE_OPERATOR_EQUALS)
-				{
-					throw new Exception('Only TREE_OPERATOR_EQUALS  operator code is supported yet for AddCondition_ReferencedBy.');
-				}
-				$oSourceFilter->AddCondition_ReferencedBy($oFilter, $sExtKeyAttCode, TREE_OPERATOR_EQUALS, $aRealiasingMap);
-			}
-			$oRet = $oSourceFilter;
-		}
-
-		return $oRet;
-	}
-
-	abstract public function SetInternalParams($aParams);
-	abstract public function GetInternalParams();
-	abstract public function GetQueryParams($bExcludeMagicParams = true);
-	abstract public function ListConstantFields();
-	
-	/**
-	 * Turn the parameters (:xxx) into scalar values in order to easily
-	 * serialize a search
-	 */
-	abstract public function ApplyParameters($aArgs);
-
-    public function serialize($bDevelopParams = false, $aContextParams = null)
-	{
-		$sOql = $this->ToOql($bDevelopParams, $aContextParams);
-		return base64_encode(serialize(array($sOql, $this->GetInternalParams(), $this->m_aModifierProperties)));
-	}
-	
-	static public function unserialize($sValue)
-	{
-		$aData = unserialize(base64_decode($sValue));
-		$sOql = $aData[0];
-		$aParams = $aData[1];
-		// We've tried to use gzcompress/gzuncompress, but for some specific queries
-		// it was not working at all (See Trac #193)
-		// gzuncompress was issuing a warning "data error" and the return object was null
-		$oRetFilter = self::FromOQL($sOql, $aParams);
-		$oRetFilter->m_aModifierProperties = $aData[2];
-		return $oRetFilter;
-	}
-
-    /**
-     * Create a new DBObjectSearch from $oSearch with a new alias $sAlias
-     *
-     * Note : This has not be tested with UNION queries.
-     *
-     * @param DBSearch $oSearch
-     * @param string $sAlias
-     * @return DBObjectSearch
-     */
-    static public function CloneWithAlias(DBSearch $oSearch, $sAlias)
-    {
-        $oSearchWithAlias = new DBObjectSearch($oSearch->GetClass(), $sAlias);
-        $oSearchWithAlias = $oSearchWithAlias->Intersect($oSearch);
-        return $oSearchWithAlias;
-    }
-
-    abstract public function ToOQL($bDevelopParams = false, $aContextParams = null, $bWithAllowAllFlag = false);
-
-	static protected $m_aOQLQueries = array();
-
-	// Do not filter out depending on user rights
-	// In particular when we are currently in the process of evaluating the user rights...
-	static public function FromOQL_AllData($sQuery, $aParams = null)
-	{
-		$oRes = self::FromOQL($sQuery, $aParams);
-		$oRes->AllowAllData();
-		return $oRes;
-	}
-
-	/**
-	 * @param string $sQuery
-	 * @param array $aParams
-	 * @return DBSearch
-	 * @throws OQLException
-	 */
-	static public function FromOQL($sQuery, $aParams = null)
-	{
-		if (empty($sQuery)) return null;
-
-		// Query caching
-		$sQueryId = md5($sQuery);
-		$bOQLCacheEnabled = true;
-		if ($bOQLCacheEnabled)
-		{
-			if (array_key_exists($sQueryId, self::$m_aOQLQueries))
-			{
-				// hit!
-				$oResultFilter = self::$m_aOQLQueries[$sQueryId]->DeepClone();
-			}
-			elseif (self::$m_bUseAPCCache)
-			{
-				// Note: For versions of APC older than 3.0.17, fetch() accepts only one parameter
-				//
-				$sAPCCacheId = 'itop-'.MetaModel::GetEnvironmentId().'-dbsearch-cache-'.$sQueryId;
-				$oKPI = new ExecutionKPI();
-				$result = apc_fetch($sAPCCacheId);
-				$oKPI->ComputeStats('Search APC (fetch)', $sQuery);
-	
-				if (is_object($result))
-				{
-					$oResultFilter = $result;
-					self::$m_aOQLQueries[$sQueryId] = $oResultFilter->DeepClone();
-				}
-			}
-		}
-
-		if (!isset($oResultFilter))
-		{
-			$oKPI = new ExecutionKPI();
-
-			$oOql = new OqlInterpreter($sQuery);
-			$oOqlQuery = $oOql->ParseQuery();
-	
-			$oMetaModel = new ModelReflectionRuntime();
-			$oOqlQuery->Check($oMetaModel, $sQuery); // Exceptions thrown in case of issue
-	
-			$oResultFilter = $oOqlQuery->ToDBSearch($sQuery);
-
-			$oKPI->ComputeStats('Parse OQL', $sQuery);
-	
-			if ($bOQLCacheEnabled)
-			{
-				self::$m_aOQLQueries[$sQueryId] = $oResultFilter->DeepClone();
-
-				if (self::$m_bUseAPCCache)
-				{
-					$oKPI = new ExecutionKPI();
-					apc_store($sAPCCacheId, $oResultFilter, self::$m_iQueryCacheTTL);
-					$oKPI->ComputeStats('Search APC (store)', $sQueryId);
-				}
-			}
-		}
-
-		if (!is_null($aParams))
-		{
-			$oResultFilter->SetInternalParams($aParams);
-		}
-		return $oResultFilter;
-	}
-
-	// Alternative to object mapping: the data are transfered directly into an array
-	// This is 10 times faster than creating a set of objects, and makes sense when optimization is required
-	/**
-	 * @param hash $aOrderBy Array of '[<classalias>.]attcode' => bAscending
-	 */	
-	public function ToDataArray($aColumns = array(), $aOrderBy = array(), $aArgs = array())
-	{
-		$sSQL = $this->MakeSelectQuery($aOrderBy, $aArgs);
-		$resQuery = CMDBSource::Query($sSQL);
-		if (!$resQuery) return;
-
-		if (count($aColumns) == 0)
-		{
-			$aColumns = array_keys(MetaModel::ListAttributeDefs($this->GetClass()));
-			// Add the standard id (as first column)
-			array_unshift($aColumns, 'id');
-		}
-
-		$aQueryCols = CMDBSource::GetColumns($resQuery);
-
-		$sClassAlias = $this->GetClassAlias();
-		$aColMap = array();
-		foreach ($aColumns as $sAttCode)
-		{
-			$sColName = $sClassAlias.$sAttCode;
-			if (in_array($sColName, $aQueryCols))
-			{
-				$aColMap[$sAttCode] = $sColName;
-			}
-		}
-
-		$aRes = array();
-		while ($aRow = CMDBSource::FetchArray($resQuery))
-		{
-			$aMappedRow = array();
-			foreach ($aColMap as $sAttCode => $sColName)
-			{
-				$aMappedRow[$sAttCode] = $aRow[$sColName];
-			}
-			$aRes[] = $aMappedRow;
-		}
-		CMDBSource::FreeResult($resQuery);
-		return $aRes;
-	}
-
-	////////////////////////////////////////////////////////////////////////////
-	//
-	// Construction of the SQL queries
-	//
-	////////////////////////////////////////////////////////////////////////////
-	protected static $m_aQueryStructCache = array();
-
-
-	public function MakeGroupByQuery($aArgs, $aGroupByExpr, $bExcludeNullValues = false)
-	{
-		if ($bExcludeNullValues)
-		{
-			// Null values are not handled (though external keys set to 0 are allowed)
-			$oQueryFilter = $this->DeepClone();
-			foreach ($aGroupByExpr as $oGroupByExp)
-			{
-				$oNull = new FunctionExpression('ISNULL', array($oGroupByExp));
-				$oNotNull = new BinaryExpression($oNull, '!=', new TrueExpression());
-				$oQueryFilter->AddConditionExpression($oNotNull);
-			}
-		}
-		else
-		{
-			$oQueryFilter = $this;
-		}
-
-		$aAttToLoad = array();
-		$oSQLQuery = $oQueryFilter->GetSQLQuery(array(), $aArgs, $aAttToLoad, null, 0, 0, false, $aGroupByExpr);
-
-		$aScalarArgs = MetaModel::PrepareQueryArguments($aArgs, $this->GetInternalParams());
-		try
-		{
-			$bBeautifulSQL = self::$m_bTraceQueries || self::$m_bDebugQuery || self::$m_bIndentQueries;
-			$sRes = $oSQLQuery->RenderGroupBy($aScalarArgs, $bBeautifulSQL);
-		}
-		catch (MissingQueryArgument $e)
-		{
-			// Add some information...
-			$e->addInfo('OQL', $this->ToOQL());
-			throw $e;
-		}
-		$this->AddQueryTraceGroupBy($aArgs, $aGroupByExpr, $sRes);
-		return $sRes;
-	}
-
-
-	/**
-	 * @param array|hash $aOrderBy Array of '[<classalias>.]attcode' => bAscending
-	 * @param array $aArgs
-	 * @param null $aAttToLoad
-	 * @param null $aExtendedDataSpec
-	 * @param int $iLimitCount
-	 * @param int $iLimitStart
-	 * @param bool $bGetCount
-	 * @return string
-	 * @throws CoreException
-	 * @throws Exception
-	 * @throws MissingQueryArgument
-	 */
-	public function MakeSelectQuery($aOrderBy = array(), $aArgs = array(), $aAttToLoad = null, $aExtendedDataSpec = null, $iLimitCount = 0, $iLimitStart = 0, $bGetCount = false)
-	{
-		// Check the order by specification, and prefix with the class alias
-		// and make sure that the ordering columns are going to be selected
-		//
-		$sClass = $this->GetClass();
-		$sClassAlias = $this->GetClassAlias();
-		$aOrderSpec = array();
-		foreach ($aOrderBy as $sFieldAlias => $bAscending)
-		{
-			if (!is_bool($bAscending))
-			{
-				throw new CoreException("Wrong direction in ORDER BY spec, found '$bAscending' and expecting a boolean value");
-			}
-
-			$iDotPos = strpos($sFieldAlias, '.');
-			if ($iDotPos === false)
-			{
-				$sAttClass = $sClass;
-				$sAttClassAlias = $sClassAlias;
-				$sAttCode = $sFieldAlias;
-			}
-			else
-			{
-				$sAttClassAlias = substr($sFieldAlias, 0, $iDotPos);
-				$sAttClass = $this->GetClassName($sAttClassAlias);
-				$sAttCode = substr($sFieldAlias, $iDotPos + 1);
-			}
-
-			if ($sAttCode != 'id')
-			{
-				MyHelpers::CheckValueInArray('field name in ORDER BY spec', $sAttCode, MetaModel::GetAttributesList($sAttClass));
-
-				$oAttDef = MetaModel::GetAttributeDef($sAttClass, $sAttCode);
-				foreach($oAttDef->GetOrderBySQLExpressions($sAttClassAlias) as $sSQLExpression)
-				{
-					$aOrderSpec[$sSQLExpression] = $bAscending;
-				}
-			}
-			else
-			{
-				$aOrderSpec['`'.$sAttClassAlias.$sAttCode.'`'] = $bAscending;
-			}
-
-			// Make sure that the columns used for sorting are present in the loaded columns
-			if (!is_null($aAttToLoad) && !isset($aAttToLoad[$sAttClassAlias][$sAttCode]))
-			{
-				$aAttToLoad[$sAttClassAlias][$sAttCode] = MetaModel::GetAttributeDef($sAttClass, $sAttCode);
-			}			
-		}
-
-		$oSQLQuery = $this->GetSQLQuery($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount);
-
-		if ($this->m_bNoContextParameters)
-		{
-			// Only internal parameters
-			$aScalarArgs = $this->GetInternalParams();
-		}
-		else
-		{
-			// The complete list of arguments will include magic arguments (e.g. current_user->attcode)
-			$aScalarArgs = MetaModel::PrepareQueryArguments($aArgs, $this->GetInternalParams());
-		}
-		try
-		{
-			$bBeautifulSQL = self::$m_bTraceQueries || self::$m_bDebugQuery || self::$m_bIndentQueries;
-			$sRes = $oSQLQuery->RenderSelect($aOrderSpec, $aScalarArgs, $iLimitCount, $iLimitStart, $bGetCount, $bBeautifulSQL);
-			if ($sClassAlias == '_itop_')
-			{
-				IssueLog::Info('SQL Query (_itop_): '.$sRes);
-			}
-		}
-		catch (MissingQueryArgument $e)
-		{
-			// Add some information...
-			$e->addInfo('OQL', $this->ToOQL());
-			throw $e;
-		}
-		$this->AddQueryTraceSelect($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $sRes);
-		return $sRes;
-	}
-
-
-	protected function GetSQLQuery($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $aGroupByExpr = null)
-	{
-		$oSQLQuery = $this->GetSQLQueryStructure($aAttToLoad, $bGetCount, $aGroupByExpr);
-		$oSQLQuery->SetSourceOQL($this->ToOQL());
-
-		// Join to an additional table, if required...
-		//
-		if ($aExtendedDataSpec != null)
-		{
-			$sTableAlias = '_extended_data_';
-			$aExtendedFields = array();
-			foreach($aExtendedDataSpec['fields'] as $sColumn)
-			{
-				$sColRef = $this->GetClassAlias().'_extdata_'.$sColumn;
-				$aExtendedFields[$sColRef] = new FieldExpressionResolved($sColumn, $sTableAlias);
-			}
-			$oSQLQueryExt = new SQLObjectQuery($aExtendedDataSpec['table'], $sTableAlias, $aExtendedFields);
-			$oSQLQuery->AddInnerJoin($oSQLQueryExt, 'id', $aExtendedDataSpec['join_key'] /*, $sTableAlias*/);
-		}
-		
-		return $oSQLQuery;
-	}
-
-	////////////////////////////////////////////////////////////////////////////
-	//
-	// Cache/Trace/Log queries
-	//
-	////////////////////////////////////////////////////////////////////////////
-	protected static $m_bDebugQuery = false;
-	protected static $m_aQueriesLog = array();
-	protected static $m_bQueryCacheEnabled = false;
-	protected static $m_bUseAPCCache = false;
-	protected static $m_iQueryCacheTTL = 3600;
-	protected static $m_bTraceQueries = false;
-	protected static $m_bIndentQueries = false;
-	protected static $m_bOptimizeQueries = false;
-
-	public static function StartDebugQuery()
-	{
-		$aBacktrace = debug_backtrace();
-		self::$m_bDebugQuery = true;
-	}
-	public static function StopDebugQuery()
-	{
-		self::$m_bDebugQuery = false;
-	}
-	
-	public static function EnableQueryCache($bEnabled, $bUseAPC, $iTimeToLive = 3600)
-	{
-		self::$m_bQueryCacheEnabled = $bEnabled;
-		self::$m_bUseAPCCache = $bUseAPC;
-		self::$m_iQueryCacheTTL = $iTimeToLive;
-	}
-	public static function EnableQueryTrace($bEnabled)
-	{
-		self::$m_bTraceQueries = $bEnabled;
-	}
-	public static function EnableQueryIndentation($bEnabled)
-	{
-		self::$m_bIndentQueries = $bEnabled;
-	}
-	public static function EnableOptimizeQuery($bEnabled)
-	{
-		self::$m_bOptimizeQueries = $bEnabled;
-	}
-
-
-	protected function AddQueryTraceSelect($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $sSql)
-	{
-		if (self::$m_bTraceQueries)
-		{
-			$aQueryData = array(
-				'type' => 'select',
-				'filter' => $this,
-				'order_by' => $aOrderBy,
-				'args' => $aArgs,
-				'att_to_load' => $aAttToLoad,
-				'extended_data_spec' => $aExtendedDataSpec,
-				'limit_count' => $iLimitCount,
-				'limit_start' => $iLimitStart,
-				'is_count' => $bGetCount
-			);
-			$sOql = $this->ToOQL(true, $aArgs);
-			self::AddQueryTrace($aQueryData, $sOql, $sSql);
-		}
-	}
-	
-	protected function AddQueryTraceGroupBy($aArgs, $aGroupByExpr, $sSql)
-	{
-		if (self::$m_bTraceQueries)
-		{
-			$aQueryData = array(
-				'type' => 'group_by',
-				'filter' => $this,
-				'args' => $aArgs,
-				'group_by_expr' => $aGroupByExpr
-			);
-			$sOql = $this->ToOQL(true, $aArgs);
-			self::AddQueryTrace($aQueryData, $sOql, $sSql);
-		}
-	}
-
-	protected static function AddQueryTrace($aQueryData, $sOql, $sSql)
-	{
-		if (self::$m_bTraceQueries)
-		{
-			$sQueryId = md5(serialize($aQueryData));
-			$sMySQLQueryId = md5($sSql);
-			if(!isset(self::$m_aQueriesLog[$sQueryId]))
-			{
-				self::$m_aQueriesLog[$sQueryId]['data'] = serialize($aQueryData);
-				self::$m_aQueriesLog[$sQueryId]['oql'] = $sOql;
-				self::$m_aQueriesLog[$sQueryId]['hits'] = 1;
-			}
-			else
-			{
-				self::$m_aQueriesLog[$sQueryId]['hits']++;
-			}
-			if(!isset(self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]))
-			{
-				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['sql'] = $sSql;
-				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['count'] = 1;
-				$iTableCount = count(CMDBSource::ExplainQuery($sSql));
-				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['table_count'] = $iTableCount;
-			}
-			else
-			{
-				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['count']++;
-			}
-		}
-	}
-
-	public static function RecordQueryTrace()
-	{
-		if (!self::$m_bTraceQueries) return;
-
-		$iOqlCount = count(self::$m_aQueriesLog);
-		$iSqlCount = 0;
-		foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
-		{
-			$iSqlCount += $aOqlData['hits'];
-		}
-		$sHtml = "<h2>Stats on SELECT queries: OQL=$iOqlCount, SQL=$iSqlCount</h2>\n";
-		foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
-		{
-			$sOql = $aOqlData['oql'];
-			$sHits = $aOqlData['hits'];
-
-			$sHtml .= "<p><b>$sHits</b> hits for OQL query: $sOql</p>\n";
-			$sHtml .= "<ul id=\"ClassesRelationships\" class=\"treeview\">\n";
-			foreach($aOqlData['queries'] as $aSqlData)
-			{
-				$sQuery = $aSqlData['sql'];
-				$sSqlHits = $aSqlData['count'];
-				$iTableCount = $aSqlData['table_count'];
-				$sHtml .= "<li><b>$sSqlHits</b> hits for SQL ($iTableCount tables): <pre style=\"font-size:60%\">$sQuery</pre></li>\n";
-			}
-			$sHtml .= "</ul>\n";
-		}
-
-		$sLogFile = 'queries.latest';
-		file_put_contents(APPROOT.'data/'.$sLogFile.'.html', $sHtml);
-
-		$sLog = "<?php\n\$aQueriesLog = ".var_export(self::$m_aQueriesLog, true).";";
-		file_put_contents(APPROOT.'data/'.$sLogFile.'.log', $sLog);
-
-		// Cumulate the queries
-		$sAllQueries = APPROOT.'data/queries.log';
-		if (file_exists($sAllQueries))
-		{
-			// Merge the new queries into the existing log
-			include($sAllQueries);
-			foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
-			{
-				if (!array_key_exists($sQueryId, $aQueriesLog))
-				{
-					$aQueriesLog[$sQueryId] = $aOqlData;
-				}
-			}
-		}
-		else
-		{
-			$aQueriesLog = self::$m_aQueriesLog;
-		}
-		$sLog = "<?php\n\$aQueriesLog = ".var_export($aQueriesLog, true).";";
-		file_put_contents($sAllQueries, $sLog);
-	}
-
-	protected static function DbgTrace($value)
-	{
-		if (!self::$m_bDebugQuery) return;
-		$aBacktrace = debug_backtrace();
-		$iCallStackPos = count($aBacktrace) - self::$m_bDebugQuery;
-		$sIndent = ""; 
-		for ($i = 0 ; $i < $iCallStackPos ; $i++)
-		{
-			$sIndent .= " .-=^=-. ";
-		}
-		$aCallers = array();
-		foreach($aBacktrace as $aStackInfo)
-		{
-			$aCallers[] = $aStackInfo["function"];
-		}
-		$sCallers = "Callstack: ".implode(', ', $aCallers);
-		$sFunction = "<b title=\"$sCallers\">".$aBacktrace[1]["function"]."</b>";
-
-		if (is_string($value))
-		{
-			echo "$sIndent$sFunction: $value<br/>\n";
-		}
-		else if (is_object($value))
-		{
-			echo "$sIndent$sFunction:\n<pre>\n";
-			print_r($value);
-			echo "</pre>\n";
-		}
-		else
-		{
-			echo "$sIndent$sFunction: $value<br/>\n";
-		}
-	}
-
-	/**
-	 * Experimental!
-	 * todo: implement the change tracking
-	 *
-	 * @param $bArchive
-	 * @throws Exception
-	 */
-	function DBBulkWriteArchiveFlag($bArchive)
-	{
-		$sClass = $this->GetClass();
-		if (!MetaModel::IsArchivable($sClass))
-		{
-			throw new Exception($sClass.' is not an archivable class');
-		}
-
-		$iFlag = $bArchive ? 1 : 0;
-
-		$oSet = new DBObjectSet($this);
-		if (MetaModel::IsStandaloneClass($sClass))
-		{
-			$oSet->OptimizeColumnLoad(array($this->GetClassAlias() => array('')));
-			$aIds = array($sClass => $oSet->GetColumnAsArray('id'));
-		}
-		else
-		{
-			$oSet->OptimizeColumnLoad(array($this->GetClassAlias() => array('finalclass')));
-			$aTemp = $oSet->GetColumnAsArray('finalclass');
-			$aIds = array();
-			foreach ($aTemp as $iObjectId => $sObjectClass)
-			{
-				$aIds[$sObjectClass][$iObjectId] = $iObjectId;
-			}
-		}
-		foreach ($aIds as $sFinalClass => $aObjectIds)
-		{
-			$sIds = implode(', ', $aObjectIds);
-
-			$sArchiveRoot = MetaModel::GetAttributeOrigin($sFinalClass, 'archive_flag');
-			$sRootTable = MetaModel::DBGetTable($sArchiveRoot);
-			$sRootKey = MetaModel::DBGetKey($sArchiveRoot);
-			$aJoins = array("`$sRootTable`");
-			$aUpdates = array();
-			foreach (MetaModel::EnumParentClasses($sFinalClass, ENUM_PARENT_CLASSES_ALL) as $sParentClass)
-			{
-				if (!MetaModel::IsValidAttCode($sParentClass, 'archive_flag')) continue;
-
-				$sTable = MetaModel::DBGetTable($sParentClass);
-				$aUpdates[] = "`$sTable`.`archive_flag` = $iFlag";
-				if ($sParentClass == $sArchiveRoot)
-				{
-					if ($bArchive)
-					{
-						// Set the date (do not change it)
-						$sDate = '"'.date(AttributeDate::GetSQLFormat()).'"';
-						$aUpdates[] = "`$sTable`.`archive_date` = coalesce(`$sTable`.`archive_date`, $sDate)";
-					}
-					else
-					{
-						// Reset the date
-						$aUpdates[] = "`$sTable`.`archive_date` = null";
-					}
-				}
-				else
-				{
-					$sKey = MetaModel::DBGetKey($sParentClass);
-					$aJoins[] = "`$sTable` ON `$sTable`.`$sKey` = `$sRootTable`.`$sRootKey`";
-				}
-			}
-			$sJoins = implode(' INNER JOIN ', $aJoins);
-			$sValues = implode(', ', $aUpdates);
-			$sUpdateQuery = "UPDATE $sJoins SET $sValues WHERE `$sRootTable`.`$sRootKey` IN ($sIds)";
-			CMDBSource::Query($sUpdateQuery);
-		}
-	}
-
-	public function UpdateContextFromUser()
-	{
-		$this->SetShowObsoleteData(utils::ShowObsoleteData());
-	}
-}
+<?php
+// Copyright (C) 2015-2017 Combodo SARL
+//
+//   This file is part of iTop.
+//
+//   iTop is free software; you can redistribute it and/or modify	
+//   it under the terms of the GNU Affero General Public License as published by
+//   the Free Software Foundation, either version 3 of the License, or
+//   (at your option) any later version.
+//
+//   iTop is distributed in the hope that it will be useful,
+//   but WITHOUT ANY WARRANTY; without even the implied warranty of
+//   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//   GNU Affero General Public License for more details.
+//
+//   You should have received a copy of the GNU Affero General Public License
+//   along with iTop. If not, see <http://www.gnu.org/licenses/>
+
+
+require_once('dbobjectsearch.class.php');
+require_once('dbunionsearch.class.php');
+
+/**
+ * An object search
+ * 
+ * Note: in the ancient times of iTop, a search was named after DBObjectSearch.
+ *  When the UNION has been introduced, it has been decided to:
+ *  - declare a hierarchy of search classes, with two leafs :
+ *    - one class to cope with a single query (A JOIN B... WHERE...)
+ *    - and the other to cope with several queries (query1 UNION query2)
+ *  - in order to preserve forward/backward compatibility of the existing modules 
+ *    - keep the name of DBObjectSearch even if it a little bit confusing
+ *    - do not provide a type-hint for function parameters defined in the modules
+ *    - leave the statements DBObjectSearch::FromOQL in the modules, though DBSearch is more relevant 
+ *
+ * @copyright   Copyright (C) 2015-2017 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+ 
+abstract class DBSearch
+{
+	const JOIN_POINTING_TO = 0;
+	const JOIN_REFERENCED_BY = 1;
+
+	protected $m_bNoContextParameters = false;
+	protected $m_aModifierProperties = array();
+	protected $m_bArchiveMode = false;
+	protected $m_bShowObsoleteData = true;
+
+	public function __construct()
+	{
+		$this->Init();
+	}
+
+	protected function Init()
+	{
+		// Set the obsolete and archive modes to the default ones
+		$this->m_bArchiveMode = utils::IsArchiveMode();
+		$this->m_bShowObsoleteData = true;
+	}
+
+	/**
+	 * Perform a deep clone (as opposed to "clone" which does copy a reference to the underlying objects)
+	 **/	 	
+	public function DeepClone()
+	{
+		return unserialize(serialize($this)); // Beware this serializes/unserializes the search and its parameters as well
+	}
+
+	abstract public function AllowAllData();
+	abstract public function IsAllDataAllowed();
+
+	public function SetArchiveMode($bEnable)
+	{
+		$this->m_bArchiveMode = $bEnable;
+	}
+	public function GetArchiveMode()
+	{
+		return $this->m_bArchiveMode;
+	}
+
+	public function SetShowObsoleteData($bShow)
+	{
+		$this->m_bShowObsoleteData = $bShow;
+	}
+	public function GetShowObsoleteData()
+	{
+		if ($this->m_bArchiveMode || $this->IsAllDataAllowed())
+		{
+			// Enable obsolete data too!
+			$bRet = true;
+		}
+		else
+		{
+			$bRet = $this->m_bShowObsoleteData;
+		}
+		return $bRet;
+	}
+
+	public function NoContextParameters() {$this->m_bNoContextParameters = true;}
+	public function HasContextParameters() {return $this->m_bNoContextParameters;}
+
+	public function SetModifierProperty($sPluginClass, $sProperty, $value)
+	{
+		$this->m_aModifierProperties[$sPluginClass][$sProperty] = $value;
+	}
+
+	public function GetModifierProperties($sPluginClass)
+	{
+		if (array_key_exists($sPluginClass, $this->m_aModifierProperties))
+		{
+			return $this->m_aModifierProperties[$sPluginClass];
+		}
+		else
+		{
+			return array();
+		}
+	}
+
+	abstract public function GetClassName($sAlias);
+	abstract public function GetClass();
+	abstract public function GetClassAlias();
+
+	/**
+	 * Change the class (only subclasses are supported as of now, because the conditions must fit the new class)
+	 * Defaults to the first selected class (most of the time it is also the first joined class	 
+	 */	 	
+	abstract public function ChangeClass($sNewClass, $sAlias = null);
+	abstract public function GetSelectedClasses();
+
+	/**
+	 * @param array $aSelectedClasses array of aliases
+	 * @throws CoreException
+	 */
+	abstract public function SetSelectedClasses($aSelectedClasses);
+
+	/**
+	 * Change any alias of the query tree
+	 *
+	 * @param $sOldName
+	 * @param $sNewName
+	 * @return bool True if the alias has been found and changed
+	 */
+	abstract public function RenameAlias($sOldName, $sNewName);
+
+	abstract public function IsAny();
+
+	public function Describe(){return 'deprecated - use ToOQL() instead';}
+	public function DescribeConditionPointTo($sExtKeyAttCode, $aPointingTo){return 'deprecated - use ToOQL() instead';}
+	public function DescribeConditionRefBy($sForeignClass, $sForeignExtKeyAttCode){return 'deprecated - use ToOQL() instead';}
+	public function DescribeConditionRelTo($aRelInfo){return 'deprecated - use ToOQL() instead';}
+	public function DescribeConditions(){return 'deprecated - use ToOQL() instead';}
+	public function __DescribeHTML(){return 'deprecated - use ToOQL() instead';}
+
+	abstract public function ResetCondition();
+	abstract public function MergeConditionExpression($oExpression);
+	abstract public function AddConditionExpression($oExpression);
+  	abstract public function AddNameCondition($sName);
+	abstract public function AddCondition($sFilterCode, $value, $sOpCode = null);
+	/**
+	 * Specify a condition on external keys or link sets
+	 * @param sAttSpec Can be either an attribute code or extkey->[sAttSpec] or linkset->[sAttSpec] and so on, recursively
+	 *                 Example: infra_list->ci_id->location_id->country	 
+	 * @param value The value to match (can be an array => IN(val1, val2...)
+	 * @return void
+	 */
+	abstract public function AddConditionAdvanced($sAttSpec, $value);
+	abstract public function AddCondition_FullText($sFullText);
+
+	/**
+	 * @param DBObjectSearch $oFilter
+	 * @param $sExtKeyAttCode
+	 * @param int $iOperatorCode
+	 * @param null $aRealiasingMap array of <old-alias> => <new-alias>, for each alias that has changed
+	 * @throws CoreException
+	 * @throws CoreWarning
+	 */
+	abstract public function AddCondition_PointingTo(DBObjectSearch $oFilter, $sExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null);
+
+	/**
+	 * @param DBObjectSearch $oFilter
+	 * @param $sForeignExtKeyAttCode
+	 * @param int $iOperatorCode
+	 * @param null $aRealiasingMap array of <old-alias> => <new-alias>, for each alias that has changed
+	 */
+	abstract public function AddCondition_ReferencedBy(DBObjectSearch $oFilter, $sForeignExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null);
+
+	abstract public function Intersect(DBSearch $oFilter);
+
+	/**
+	 * @param DBSearch $oFilter
+	 * @param integer $iDirection
+	 * @param string $sExtKeyAttCode
+	 * @param integer $iOperatorCode
+	 * @param array &$RealisasingMap  Map of aliases from the attached query, that could have been renamed by the optimization process
+	 * @return DBSearch
+	 */
+	public function Join(DBSearch $oFilter, $iDirection, $sExtKeyAttCode, $iOperatorCode = TREE_OPERATOR_EQUALS, &$aRealiasingMap = null)
+	{
+		$oSourceFilter = $this->DeepClone();
+		$oRet = null;
+
+		if ($oFilter instanceof DBUnionSearch)
+		{
+			$aSearches = array();
+			foreach ($oFilter->GetSearches() as $oSearch)
+			{
+				$aSearches[] = $oSourceFilter->Join($oSearch, $iDirection, $sExtKeyAttCode, $iOperatorCode, $aRealiasingMap);
+			}
+			$oRet = new DBUnionSearch($aSearches);
+		}
+		else
+		{
+			if ($iDirection === static::JOIN_POINTING_TO)
+			{
+				$oSourceFilter->AddCondition_PointingTo($oFilter, $sExtKeyAttCode, $iOperatorCode, $aRealiasingMap);
+			}
+			else
+			{
+				if ($iOperatorCode !== TREE_OPERATOR_EQUALS)
+				{
+					throw new Exception('Only TREE_OPERATOR_EQUALS  operator code is supported yet for AddCondition_ReferencedBy.');
+				}
+				$oSourceFilter->AddCondition_ReferencedBy($oFilter, $sExtKeyAttCode, TREE_OPERATOR_EQUALS, $aRealiasingMap);
+			}
+			$oRet = $oSourceFilter;
+		}
+
+		return $oRet;
+	}
+
+	abstract public function SetInternalParams($aParams);
+	abstract public function GetInternalParams();
+	abstract public function GetQueryParams($bExcludeMagicParams = true);
+	abstract public function ListConstantFields();
+	
+	/**
+	 * Turn the parameters (:xxx) into scalar values in order to easily
+	 * serialize a search
+	 */
+	abstract public function ApplyParameters($aArgs);
+
+    public function serialize($bDevelopParams = false, $aContextParams = null)
+	{
+		$sOql = $this->ToOql($bDevelopParams, $aContextParams);
+		return base64_encode(serialize(array($sOql, $this->GetInternalParams(), $this->m_aModifierProperties)));
+	}
+
+	/**
+	 * @param string $sValue Serialized OQL query
+	 *
+	 * @return \DBSearch
+	 */
+	static public function unserialize($sValue)
+	{
+		$aData = unserialize(base64_decode($sValue));
+		$sOql = $aData[0];
+		$aParams = $aData[1];
+		// We've tried to use gzcompress/gzuncompress, but for some specific queries
+		// it was not working at all (See Trac #193)
+		// gzuncompress was issuing a warning "data error" and the return object was null
+		$oRetFilter = self::FromOQL($sOql, $aParams);
+		$oRetFilter->m_aModifierProperties = $aData[2];
+		return $oRetFilter;
+	}
+
+    /**
+     * Create a new DBObjectSearch from $oSearch with a new alias $sAlias
+     *
+     * Note : This has not be tested with UNION queries.
+     *
+     * @param DBSearch $oSearch
+     * @param string $sAlias
+     * @return DBObjectSearch
+     */
+    static public function CloneWithAlias(DBSearch $oSearch, $sAlias)
+    {
+        $oSearchWithAlias = new DBObjectSearch($oSearch->GetClass(), $sAlias);
+        $oSearchWithAlias = $oSearchWithAlias->Intersect($oSearch);
+        return $oSearchWithAlias;
+    }
+
+    abstract public function ToOQL($bDevelopParams = false, $aContextParams = null, $bWithAllowAllFlag = false);
+
+	static protected $m_aOQLQueries = array();
+
+	// Do not filter out depending on user rights
+	// In particular when we are currently in the process of evaluating the user rights...
+	static public function FromOQL_AllData($sQuery, $aParams = null)
+	{
+		$oRes = self::FromOQL($sQuery, $aParams);
+		$oRes->AllowAllData();
+		return $oRes;
+	}
+
+	/**
+	 * @param string $sQuery
+	 * @param array $aParams
+	 * @return DBSearch
+	 * @throws OQLException
+	 */
+	static public function FromOQL($sQuery, $aParams = null)
+	{
+		if (empty($sQuery))
+		{
+			return null;
+		}
+
+		// Query caching
+		$sQueryId = md5($sQuery);
+		$bOQLCacheEnabled = true;
+		if ($bOQLCacheEnabled)
+		{
+			if (array_key_exists($sQueryId, self::$m_aOQLQueries))
+			{
+				// hit!
+				$oResultFilter = self::$m_aOQLQueries[$sQueryId]->DeepClone();
+			}
+			elseif (self::$m_bUseAPCCache)
+			{
+				// Note: For versions of APC older than 3.0.17, fetch() accepts only one parameter
+				//
+				$sAPCCacheId = 'itop-'.MetaModel::GetEnvironmentId().'-dbsearch-cache-'.$sQueryId;
+				$oKPI = new ExecutionKPI();
+				$result = apc_fetch($sAPCCacheId);
+				$oKPI->ComputeStats('Search APC (fetch)', $sQuery);
+	
+				if (is_object($result))
+				{
+					$oResultFilter = $result;
+					self::$m_aOQLQueries[$sQueryId] = $oResultFilter->DeepClone();
+				}
+			}
+		}
+
+		if (!isset($oResultFilter))
+		{
+			$oKPI = new ExecutionKPI();
+
+			$oOql = new OqlInterpreter($sQuery);
+			$oOqlQuery = $oOql->ParseQuery();
+	
+			$oMetaModel = new ModelReflectionRuntime();
+			$oOqlQuery->Check($oMetaModel, $sQuery); // Exceptions thrown in case of issue
+	
+			$oResultFilter = $oOqlQuery->ToDBSearch($sQuery);
+
+			$oKPI->ComputeStats('Parse OQL', $sQuery);
+	
+			if ($bOQLCacheEnabled)
+			{
+				self::$m_aOQLQueries[$sQueryId] = $oResultFilter->DeepClone();
+
+				if (self::$m_bUseAPCCache)
+				{
+					$oKPI = new ExecutionKPI();
+					apc_store($sAPCCacheId, $oResultFilter, self::$m_iQueryCacheTTL);
+					$oKPI->ComputeStats('Search APC (store)', $sQueryId);
+				}
+			}
+		}
+
+		if (!is_null($aParams))
+		{
+			$oResultFilter->SetInternalParams($aParams);
+		}
+
+		// Set the default fields
+		$oResultFilter->Init();
+
+		return $oResultFilter;
+	}
+
+	// Alternative to object mapping: the data are transfered directly into an array
+	// This is 10 times faster than creating a set of objects, and makes sense when optimization is required
+	/**
+	 * @param hash $aOrderBy Array of '[<classalias>.]attcode' => bAscending
+	 */	
+	public function ToDataArray($aColumns = array(), $aOrderBy = array(), $aArgs = array())
+	{
+		$sSQL = $this->MakeSelectQuery($aOrderBy, $aArgs);
+		$resQuery = CMDBSource::Query($sSQL);
+		if (!$resQuery)
+		{
+			return;
+		}
+
+		if (count($aColumns) == 0)
+		{
+			$aColumns = array_keys(MetaModel::ListAttributeDefs($this->GetClass()));
+			// Add the standard id (as first column)
+			array_unshift($aColumns, 'id');
+		}
+
+		$aQueryCols = CMDBSource::GetColumns($resQuery);
+
+		$sClassAlias = $this->GetClassAlias();
+		$aColMap = array();
+		foreach ($aColumns as $sAttCode)
+		{
+			$sColName = $sClassAlias.$sAttCode;
+			if (in_array($sColName, $aQueryCols))
+			{
+				$aColMap[$sAttCode] = $sColName;
+			}
+		}
+
+		$aRes = array();
+		while ($aRow = CMDBSource::FetchArray($resQuery))
+		{
+			$aMappedRow = array();
+			foreach ($aColMap as $sAttCode => $sColName)
+			{
+				$aMappedRow[$sAttCode] = $aRow[$sColName];
+			}
+			$aRes[] = $aMappedRow;
+		}
+		CMDBSource::FreeResult($resQuery);
+		return $aRes;
+	}
+
+	////////////////////////////////////////////////////////////////////////////
+	//
+	// Construction of the SQL queries
+	//
+	////////////////////////////////////////////////////////////////////////////
+	protected static $m_aQueryStructCache = array();
+
+
+	public function MakeGroupByQuery($aArgs, $aGroupByExpr, $bExcludeNullValues = false)
+	{
+		if ($bExcludeNullValues)
+		{
+			// Null values are not handled (though external keys set to 0 are allowed)
+			$oQueryFilter = $this->DeepClone();
+			foreach ($aGroupByExpr as $oGroupByExp)
+			{
+				$oNull = new FunctionExpression('ISNULL', array($oGroupByExp));
+				$oNotNull = new BinaryExpression($oNull, '!=', new TrueExpression());
+				$oQueryFilter->AddConditionExpression($oNotNull);
+			}
+		}
+		else
+		{
+			$oQueryFilter = $this;
+		}
+
+		$aAttToLoad = array();
+		$oSQLQuery = $oQueryFilter->GetSQLQuery(array(), $aArgs, $aAttToLoad, null, 0, 0, false, $aGroupByExpr);
+
+		$aScalarArgs = MetaModel::PrepareQueryArguments($aArgs, $this->GetInternalParams());
+		try
+		{
+			$bBeautifulSQL = self::$m_bTraceQueries || self::$m_bDebugQuery || self::$m_bIndentQueries;
+			$sRes = $oSQLQuery->RenderGroupBy($aScalarArgs, $bBeautifulSQL);
+		}
+		catch (MissingQueryArgument $e)
+		{
+			// Add some information...
+			$e->addInfo('OQL', $this->ToOQL());
+			throw $e;
+		}
+		$this->AddQueryTraceGroupBy($aArgs, $aGroupByExpr, $sRes);
+		return $sRes;
+	}
+
+
+	/**
+	 * @param array|hash $aOrderBy Array of '[<classalias>.]attcode' => bAscending
+	 * @param array $aArgs
+	 * @param null $aAttToLoad
+	 * @param null $aExtendedDataSpec
+	 * @param int $iLimitCount
+	 * @param int $iLimitStart
+	 * @param bool $bGetCount
+	 * @return string
+	 * @throws CoreException
+	 * @throws Exception
+	 * @throws MissingQueryArgument
+	 */
+	public function MakeSelectQuery($aOrderBy = array(), $aArgs = array(), $aAttToLoad = null, $aExtendedDataSpec = null, $iLimitCount = 0, $iLimitStart = 0, $bGetCount = false)
+	{
+		// Check the order by specification, and prefix with the class alias
+		// and make sure that the ordering columns are going to be selected
+		//
+		$sClass = $this->GetClass();
+		$sClassAlias = $this->GetClassAlias();
+		$aOrderSpec = array();
+		foreach ($aOrderBy as $sFieldAlias => $bAscending)
+		{
+			if (!is_bool($bAscending))
+			{
+				throw new CoreException("Wrong direction in ORDER BY spec, found '$bAscending' and expecting a boolean value");
+			}
+
+			$iDotPos = strpos($sFieldAlias, '.');
+			if ($iDotPos === false)
+			{
+				$sAttClass = $sClass;
+				$sAttClassAlias = $sClassAlias;
+				$sAttCode = $sFieldAlias;
+			}
+			else
+			{
+				$sAttClassAlias = substr($sFieldAlias, 0, $iDotPos);
+				$sAttClass = $this->GetClassName($sAttClassAlias);
+				$sAttCode = substr($sFieldAlias, $iDotPos + 1);
+			}
+
+			if ($sAttCode != 'id')
+			{
+				MyHelpers::CheckValueInArray('field name in ORDER BY spec', $sAttCode, MetaModel::GetAttributesList($sAttClass));
+
+				$oAttDef = MetaModel::GetAttributeDef($sAttClass, $sAttCode);
+				foreach($oAttDef->GetOrderBySQLExpressions($sAttClassAlias) as $sSQLExpression)
+				{
+					$aOrderSpec[$sSQLExpression] = $bAscending;
+				}
+			}
+			else
+			{
+				$aOrderSpec['`'.$sAttClassAlias.$sAttCode.'`'] = $bAscending;
+			}
+
+			// Make sure that the columns used for sorting are present in the loaded columns
+			if (!is_null($aAttToLoad) && !isset($aAttToLoad[$sAttClassAlias][$sAttCode]))
+			{
+				$aAttToLoad[$sAttClassAlias][$sAttCode] = MetaModel::GetAttributeDef($sAttClass, $sAttCode);
+			}			
+		}
+
+		$oSQLQuery = $this->GetSQLQuery($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount);
+
+		if ($this->m_bNoContextParameters)
+		{
+			// Only internal parameters
+			$aScalarArgs = $this->GetInternalParams();
+		}
+		else
+		{
+			// The complete list of arguments will include magic arguments (e.g. current_user->attcode)
+			$aScalarArgs = MetaModel::PrepareQueryArguments($aArgs, $this->GetInternalParams());
+		}
+		try
+		{
+			$bBeautifulSQL = self::$m_bTraceQueries || self::$m_bDebugQuery || self::$m_bIndentQueries;
+			$sRes = $oSQLQuery->RenderSelect($aOrderSpec, $aScalarArgs, $iLimitCount, $iLimitStart, $bGetCount, $bBeautifulSQL);
+			if ($sClassAlias == '_itop_')
+			{
+				IssueLog::Info('SQL Query (_itop_): '.$sRes);
+			}
+		}
+		catch (MissingQueryArgument $e)
+		{
+			// Add some information...
+			$e->addInfo('OQL', $this->ToOQL());
+			throw $e;
+		}
+		$this->AddQueryTraceSelect($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $sRes);
+		return $sRes;
+	}
+
+
+	protected function GetSQLQuery($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $aGroupByExpr = null)
+	{
+		$oSQLQuery = $this->GetSQLQueryStructure($aAttToLoad, $bGetCount, $aGroupByExpr);
+		$oSQLQuery->SetSourceOQL($this->ToOQL());
+
+		// Join to an additional table, if required...
+		//
+		if ($aExtendedDataSpec != null)
+		{
+			$sTableAlias = '_extended_data_';
+			$aExtendedFields = array();
+			foreach($aExtendedDataSpec['fields'] as $sColumn)
+			{
+				$sColRef = $this->GetClassAlias().'_extdata_'.$sColumn;
+				$aExtendedFields[$sColRef] = new FieldExpressionResolved($sColumn, $sTableAlias);
+			}
+			$oSQLQueryExt = new SQLObjectQuery($aExtendedDataSpec['table'], $sTableAlias, $aExtendedFields);
+			$oSQLQuery->AddInnerJoin($oSQLQueryExt, 'id', $aExtendedDataSpec['join_key'] /*, $sTableAlias*/);
+		}
+		
+		return $oSQLQuery;
+	}
+
+	public abstract function GetSQLQueryStructure(
+		$aAttToLoad, $bGetCount, $aGroupByExpr = null, $aSelectedClasses = null
+	);
+
+	////////////////////////////////////////////////////////////////////////////
+	//
+	// Cache/Trace/Log queries
+	//
+	////////////////////////////////////////////////////////////////////////////
+	protected static $m_bDebugQuery = false;
+	protected static $m_aQueriesLog = array();
+	protected static $m_bQueryCacheEnabled = false;
+	protected static $m_bUseAPCCache = false;
+	protected static $m_iQueryCacheTTL = 3600;
+	protected static $m_bTraceQueries = false;
+	protected static $m_bIndentQueries = false;
+	protected static $m_bOptimizeQueries = false;
+
+	public static function StartDebugQuery()
+	{
+		$aBacktrace = debug_backtrace();
+		self::$m_bDebugQuery = true;
+	}
+	public static function StopDebugQuery()
+	{
+		self::$m_bDebugQuery = false;
+	}
+	
+	public static function EnableQueryCache($bEnabled, $bUseAPC, $iTimeToLive = 3600)
+	{
+		self::$m_bQueryCacheEnabled = $bEnabled;
+		self::$m_bUseAPCCache = $bUseAPC;
+		self::$m_iQueryCacheTTL = $iTimeToLive;
+	}
+	public static function EnableQueryTrace($bEnabled)
+	{
+		self::$m_bTraceQueries = $bEnabled;
+	}
+	public static function EnableQueryIndentation($bEnabled)
+	{
+		self::$m_bIndentQueries = $bEnabled;
+	}
+	public static function EnableOptimizeQuery($bEnabled)
+	{
+		self::$m_bOptimizeQueries = $bEnabled;
+	}
+
+
+	protected function AddQueryTraceSelect($aOrderBy, $aArgs, $aAttToLoad, $aExtendedDataSpec, $iLimitCount, $iLimitStart, $bGetCount, $sSql)
+	{
+		if (self::$m_bTraceQueries)
+		{
+			$aQueryData = array(
+				'type' => 'select',
+				'filter' => $this,
+				'order_by' => $aOrderBy,
+				'args' => $aArgs,
+				'att_to_load' => $aAttToLoad,
+				'extended_data_spec' => $aExtendedDataSpec,
+				'limit_count' => $iLimitCount,
+				'limit_start' => $iLimitStart,
+				'is_count' => $bGetCount
+			);
+			$sOql = $this->ToOQL(true, $aArgs);
+			self::AddQueryTrace($aQueryData, $sOql, $sSql);
+		}
+	}
+	
+	protected function AddQueryTraceGroupBy($aArgs, $aGroupByExpr, $sSql)
+	{
+		if (self::$m_bTraceQueries)
+		{
+			$aQueryData = array(
+				'type' => 'group_by',
+				'filter' => $this,
+				'args' => $aArgs,
+				'group_by_expr' => $aGroupByExpr
+			);
+			$sOql = $this->ToOQL(true, $aArgs);
+			self::AddQueryTrace($aQueryData, $sOql, $sSql);
+		}
+	}
+
+	protected static function AddQueryTrace($aQueryData, $sOql, $sSql)
+	{
+		if (self::$m_bTraceQueries)
+		{
+			$sQueryId = md5(serialize($aQueryData));
+			$sMySQLQueryId = md5($sSql);
+			if(!isset(self::$m_aQueriesLog[$sQueryId]))
+			{
+				self::$m_aQueriesLog[$sQueryId]['data'] = serialize($aQueryData);
+				self::$m_aQueriesLog[$sQueryId]['oql'] = $sOql;
+				self::$m_aQueriesLog[$sQueryId]['hits'] = 1;
+			}
+			else
+			{
+				self::$m_aQueriesLog[$sQueryId]['hits']++;
+			}
+			if(!isset(self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]))
+			{
+				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['sql'] = $sSql;
+				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['count'] = 1;
+				$iTableCount = count(CMDBSource::ExplainQuery($sSql));
+				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['table_count'] = $iTableCount;
+			}
+			else
+			{
+				self::$m_aQueriesLog[$sQueryId]['queries'][$sMySQLQueryId]['count']++;
+			}
+		}
+	}
+
+	public static function RecordQueryTrace()
+	{
+		if (!self::$m_bTraceQueries)
+		{
+			return;
+		}
+
+		$iOqlCount = count(self::$m_aQueriesLog);
+		$iSqlCount = 0;
+		foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
+		{
+			$iSqlCount += $aOqlData['hits'];
+		}
+		$sHtml = "<h2>Stats on SELECT queries: OQL=$iOqlCount, SQL=$iSqlCount</h2>\n";
+		foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
+		{
+			$sOql = $aOqlData['oql'];
+			$sHits = $aOqlData['hits'];
+
+			$sHtml .= "<p><b>$sHits</b> hits for OQL query: $sOql</p>\n";
+			$sHtml .= "<ul id=\"ClassesRelationships\" class=\"treeview\">\n";
+			foreach($aOqlData['queries'] as $aSqlData)
+			{
+				$sQuery = $aSqlData['sql'];
+				$sSqlHits = $aSqlData['count'];
+				$iTableCount = $aSqlData['table_count'];
+				$sHtml .= "<li><b>$sSqlHits</b> hits for SQL ($iTableCount tables): <pre style=\"font-size:60%\">$sQuery</pre></li>\n";
+			}
+			$sHtml .= "</ul>\n";
+		}
+
+		$sLogFile = 'queries.latest';
+		file_put_contents(APPROOT.'data/'.$sLogFile.'.html', $sHtml);
+
+		$sLog = "<?php\n\$aQueriesLog = ".var_export(self::$m_aQueriesLog, true).";";
+		file_put_contents(APPROOT.'data/'.$sLogFile.'.log', $sLog);
+
+		// Cumulate the queries
+		$sAllQueries = APPROOT.'data/queries.log';
+		if (file_exists($sAllQueries))
+		{
+			// Merge the new queries into the existing log
+			include($sAllQueries);
+			$aQueriesLog = array();
+			foreach (self::$m_aQueriesLog as $sQueryId => $aOqlData)
+			{
+				if (!array_key_exists($sQueryId, $aQueriesLog))
+				{
+					$aQueriesLog[$sQueryId] = $aOqlData;
+				}
+			}
+		}
+		else
+		{
+			$aQueriesLog = self::$m_aQueriesLog;
+		}
+		$sLog = "<?php\n\$aQueriesLog = ".var_export($aQueriesLog, true).";";
+		file_put_contents($sAllQueries, $sLog);
+	}
+
+	protected static function DbgTrace($value)
+	{
+		if (!self::$m_bDebugQuery)
+		{
+			return;
+		}
+		$aBacktrace = debug_backtrace();
+		$iCallStackPos = count($aBacktrace) - self::$m_bDebugQuery;
+		$sIndent = ""; 
+		for ($i = 0 ; $i < $iCallStackPos ; $i++)
+		{
+			$sIndent .= " .-=^=-. ";
+		}
+		$aCallers = array();
+		foreach($aBacktrace as $aStackInfo)
+		{
+			$aCallers[] = $aStackInfo["function"];
+		}
+		$sCallers = "Callstack: ".implode(', ', $aCallers);
+		$sFunction = "<b title=\"$sCallers\">".$aBacktrace[1]["function"]."</b>";
+
+		if (is_object($value))
+		{
+			echo "$sIndent$sFunction:\n<pre>\n";
+			print_r($value);
+			echo "</pre>\n";
+		}
+		else
+		{
+			echo "$sIndent$sFunction: $value<br/>\n";
+		}
+	}
+
+	/**
+	 * Experimental!
+	 * todo: implement the change tracking
+	 *
+	 * @param $bArchive
+	 * @throws Exception
+	 */
+	function DBBulkWriteArchiveFlag($bArchive)
+	{
+		$sClass = $this->GetClass();
+		if (!MetaModel::IsArchivable($sClass))
+		{
+			throw new Exception($sClass.' is not an archivable class');
+		}
+
+		$iFlag = $bArchive ? 1 : 0;
+
+		$oSet = new DBObjectSet($this);
+		if (MetaModel::IsStandaloneClass($sClass))
+		{
+			$oSet->OptimizeColumnLoad(array($this->GetClassAlias() => array('')));
+			$aIds = array($sClass => $oSet->GetColumnAsArray('id'));
+		}
+		else
+		{
+			$oSet->OptimizeColumnLoad(array($this->GetClassAlias() => array('finalclass')));
+			$aTemp = $oSet->GetColumnAsArray('finalclass');
+			$aIds = array();
+			foreach ($aTemp as $iObjectId => $sObjectClass)
+			{
+				$aIds[$sObjectClass][$iObjectId] = $iObjectId;
+			}
+		}
+		foreach ($aIds as $sFinalClass => $aObjectIds)
+		{
+			$sIds = implode(', ', $aObjectIds);
+
+			$sArchiveRoot = MetaModel::GetAttributeOrigin($sFinalClass, 'archive_flag');
+			$sRootTable = MetaModel::DBGetTable($sArchiveRoot);
+			$sRootKey = MetaModel::DBGetKey($sArchiveRoot);
+			$aJoins = array("`$sRootTable`");
+			$aUpdates = array();
+			foreach (MetaModel::EnumParentClasses($sFinalClass, ENUM_PARENT_CLASSES_ALL) as $sParentClass)
+			{
+				if (!MetaModel::IsValidAttCode($sParentClass, 'archive_flag'))
+				{
+					continue;
+				}
+
+				$sTable = MetaModel::DBGetTable($sParentClass);
+				$aUpdates[] = "`$sTable`.`archive_flag` = $iFlag";
+				if ($sParentClass == $sArchiveRoot)
+				{
+					if ($bArchive)
+					{
+						// Set the date (do not change it)
+						$sDate = '"'.date(AttributeDate::GetSQLFormat()).'"';
+						$aUpdates[] = "`$sTable`.`archive_date` = coalesce(`$sTable`.`archive_date`, $sDate)";
+					}
+					else
+					{
+						// Reset the date
+						$aUpdates[] = "`$sTable`.`archive_date` = null";
+					}
+				}
+				else
+				{
+					$sKey = MetaModel::DBGetKey($sParentClass);
+					$aJoins[] = "`$sTable` ON `$sTable`.`$sKey` = `$sRootTable`.`$sRootKey`";
+				}
+			}
+			$sJoins = implode(' INNER JOIN ', $aJoins);
+			$sValues = implode(', ', $aUpdates);
+			$sUpdateQuery = "UPDATE $sJoins SET $sValues WHERE `$sRootTable`.`$sRootKey` IN ($sIds)";
+			CMDBSource::Query($sUpdateQuery);
+		}
+	}
+
+	public function UpdateContextFromUser()
+	{
+		$this->SetShowObsoleteData(utils::ShowObsoleteData());
+	}
+}
diff --git a/pages/ajax.render.php b/pages/ajax.render.php
index adedcad2f..92973735c 100644
--- a/pages/ajax.render.php
+++ b/pages/ajax.render.php
@@ -2155,6 +2155,7 @@ EOF
 				if ($sExpression === null)
 				{
 					$oQuerySearch = DBObjectSearch::FromOQL('SELECT QueryOQL WHERE id = :query_id', array('query_id' => $iQueryId));
+					$oQuerySearch->UpdateContextFromUser();
 					$oQueries = new DBObjectSet($oQuerySearch);
 					if ($oQueries->Count() > 0)
 					{
@@ -2169,6 +2170,7 @@ EOF
 				if($sExpression !== null)
 				{ 
 					$oSearch = DBObjectSearch::FromOQL($sExpression);
+					$oSearch->UpdateContextFromUser();
 					$oExporter = BulkExport::FindExporter($sFormat, $oSearch);
 					$oExporter->SetObjectList($oSearch);
 					$oExporter->SetFormat($sFormat);
diff --git a/pages/audit.php b/pages/audit.php
index ff7edd158..1ac3cd6f7 100644
--- a/pages/audit.php
+++ b/pages/audit.php
@@ -88,6 +88,7 @@ function GetRuleResultFilter($iRuleId, $oDefinitionFilter, $oAppContext)
 	$oRule = MetaModel::GetObject('AuditRule', $iRuleId);
 	$sOql = $oRule->Get('query');
 	$oRuleFilter = DBObjectSearch::FromOQL($sOql);
+	$oRuleFilter->UpdateContextFromUser();
 	FilterByContext($oRuleFilter, $oAppContext); // Not needed since this filter is a subset of the definition filter, but may speedup things
 
 	if ($oRule->Get('valid_flag') == 'false')
@@ -168,6 +169,7 @@ try
 	
 		$oAuditCategory = MetaModel::GetObject('AuditCategory', $iCategory);
 		$oDefinitionFilter = DBObjectSearch::FromOQL($oAuditCategory->Get('definition_set'));
+		$oDefinitionFilter->UpdateContextFromUser();
 		FilterByContext($oDefinitionFilter, $oAppContext);
 		$oDefinitionSet = new CMDBObjectSet($oDefinitionFilter);
 		$oFilter = GetRuleResultFilter($iRuleIndex, $oDefinitionFilter, $oAppContext);
@@ -232,6 +234,7 @@ try
 	
 		$oAuditCategory = MetaModel::GetObject('AuditCategory', $iCategory);
 		$oDefinitionFilter = DBObjectSearch::FromOQL($oAuditCategory->Get('definition_set'));
+		$oDefinitionFilter->UpdateContextFromUser();
 		FilterByContext($oDefinitionFilter, $oAppContext);
 		$oDefinitionSet = new CMDBObjectSet($oDefinitionFilter);
 		$oFilter = GetRuleResultFilter($iRuleIndex, $oDefinitionFilter, $oAppContext);
@@ -265,6 +268,7 @@ try
 			try
 			{
 				$oDefinitionFilter = DBObjectSearch::FromOQL($oAuditCategory->Get('definition_set'));
+				$oDefinitionFilter->UpdateContextFromUser();
 				FilterByContext($oDefinitionFilter, $oAppContext);
 				
 				$aObjectsWithErrors = array();
diff --git a/webservices/export-v2.php b/webservices/export-v2.php
index b58ee36df..157eec5ab 100644
--- a/webservices/export-v2.php
+++ b/webservices/export-v2.php
@@ -137,6 +137,7 @@ function DisplayExpressionForm(WebPage $oP, $sAction, $sExpression = '', $sExcep
 	$oP->add('<td><select name="query" id="select_phrasebook">');
 	$oP->add('<option value="">'.Dict::S('UI:SelectOne').'</option>');
 	$oSearch = DBObjectSearch::FromOQL('SELECT QueryOQL');
+    $oSearch->UpdateContextFromUser();
 	$oQueries = new DBObjectSet($oSearch);
 	while ($oQuery = $oQueries->Fetch())
 	{
@@ -239,6 +240,7 @@ EOF
 		try
 		{
 			$oExportSearch = DBObjectSearch::FromOQL($sExpression);
+			$oExportSearch->UpdateContextFromUser();
 		}
 		catch(OQLException $e)
 		{
@@ -257,11 +259,13 @@ EOF
 	{
 		$oP->add('<input type="hidden" name="expression" value="'.htmlentities($sExpression, ENT_QUOTES, 'UTF-8').'">');
 		$oExportSearch = DBObjectSearch::FromOQL($sExpression);
+        $oExportSearch->UpdateContextFromUser();
 	}
 	else
 	{
 		$oQuery = MetaModel::GetObject('QueryOQL', $sQueryId);
 		$oExportSearch = DBObjectSearch::FromOQL($oQuery->Get('oql'));
+        $oExportSearch->UpdateContextFromUser();
 		$oP->add('<input type="hidden" name="query" value="'.htmlentities($sQueryId, ENT_QUOTES, 'UTF-8').'">');
 	}
 	$aFormPartsByFormat = array();
@@ -379,6 +383,7 @@ EOF
 		if ($sQueryId !== null)
 		{
 			$oSearch = DBObjectSearch::FromOQL('SELECT QueryOQL WHERE id = :query_id', array('query_id' => $sQueryId));
+            $oSearch->UpdateContextFromUser();
 			$oQueries = new DBObjectSet($oSearch);
 			if ($oQueries->Count() > 0)
 			{
@@ -406,6 +411,7 @@ EOF
 			}
 		}
 	}
+
 	
 	if ($sFormat !== null)
 	{
@@ -458,7 +464,8 @@ function CheckParameters($sExpression, $sQueryId, $sFormat)
 	if ($sExpression === null)
 	{
 		$oSearch = DBObjectSearch::FromOQL('SELECT QueryOQL WHERE id = :query_id', array('query_id' => $sQueryId));
-		$oQueries = new DBObjectSet($oSearch);
+        $oSearch->UpdateContextFromUser();
+        $oQueries = new DBObjectSet($oSearch);
 		if ($oQueries->Count() > 0)
 		{
 			$oQuery = $oQueries->Fetch();
@@ -478,6 +485,7 @@ function CheckParameters($sExpression, $sQueryId, $sFormat)
 	try
 	{
 		$oSearch = DBObjectSearch::FromOQL($sExpression);
+        $oSearch->UpdateContextFromUser();
 		$aArgs = array();
 		foreach($oSearch->GetQueryParams() as $sParam => $foo)
 		{
@@ -608,6 +616,7 @@ if (utils::IsModeCLI())
 	if ($sExpression === null)
 	{
 		$oSearch = DBObjectSearch::FromOQL('SELECT QueryOQL WHERE id = :query_id', array('query_id' => $sQueryId));
+        $oSearch->UpdateContextFromUser();
 		$oQueries = new DBObjectSet($oSearch);
 		if ($oQueries->Count() > 0)
 		{
@@ -622,6 +631,7 @@ if (utils::IsModeCLI())
 	try
 	{
 		$oSearch = DBObjectSearch::FromOQL($sExpression);
+        $oSearch->UpdateContextFromUser();
 		$aArgs = array();
 		foreach($oSearch->GetQueryParams() as $sParam => $foo)
 		{