diff --git a/core/cmdbsource.class.inc.php b/core/cmdbsource.class.inc.php
index 50a5e1ab4..1f71e33d9 100644
--- a/core/cmdbsource.class.inc.php
+++ b/core/cmdbsource.class.inc.php
@@ -68,6 +68,7 @@ class CMDBSource
 
 	/** @var mysqli $m_oMysqli */
 	protected static $m_oMysqli;
+	protected static $oMySQLiForQuery;
 
 	/**
 	 * @var int number of level for nested transactions : 0 if no transaction was ever opened, +1 for each 'START TRANSACTION' sent
@@ -134,6 +135,7 @@ class CMDBSource
 		self::$m_sDBTlsCA = empty($sTlsCA) ? null : $sTlsCA;
 
 		self::$m_oMysqli = self::GetMysqliInstance($sServer, $sUser, $sPwd, $sSource, $bTlsEnabled, $sTlsCA, true);
+		self::SetMySQLiForQuery(self::$m_oMysqli);
 	}
 
 	/**
@@ -151,8 +153,6 @@ class CMDBSource
 	public static function GetMysqliInstance(
 		$sDbHost, $sUser, $sPwd, $sSource = '', $bTlsEnabled = false, $sTlsCa = null, $bCheckTlsAfterConnection = false
 	) {
-		$oMysqli = null;
-
 		$sServer = null;
 		$iPort = null;
 		self::InitServerAndPort($sDbHost, $sServer, $iPort);
@@ -450,6 +450,24 @@ class CMDBSource
 		return self::$m_oMysqli;
 	}
 
+	/**
+	 * @return
+	 */
+	private static function GetMySQLiForQuery()
+	{
+		return self::$oMySQLiForQuery;
+	}
+
+
+	/**
+	 * Used for test purpose (mysqli mock)
+	 * @param $oMySQLi
+	 */
+	private static function SetMySQLiForQuery($oMySQLi)
+	{
+		self::$oMySQLiForQuery = $oMySQLi;
+	}
+
 	public static function GetErrNo()
 	{
 		if (self::$m_oMysqli->errno != 0)
@@ -585,7 +603,7 @@ class CMDBSource
 	 */
 	private static function DBQuery($sSql)
 	{
-		$sShortSQL = str_replace("\n", " ", substr($sSql, 0, 120));
+		$sShortSQL = substr(preg_replace("/\s+/", " ", substr($sSql, 0, 180)), 0, 150);
 		if (substr_compare($sShortSQL, "SELECT", 0, strlen("SELECT")) !== 0) {
 			IssueLog::Trace("$sShortSQL", 'cmdbsource');
 		}
@@ -593,7 +611,7 @@ class CMDBSource
 		$oKPI = new ExecutionKPI();
 		try
 		{
-			$oResult = self::$m_oMysqli->query($sSql);
+			$oResult = self::GetMySQLiForQuery()->query($sSql);
 		}
 		catch (mysqli_sql_exception $e)
 		{
@@ -657,7 +675,7 @@ class CMDBSource
 		);
 		DeadLockLog::Info($sMessage, $iMySqlErrorNo, $aLogContext);
 
-		IssueLog::Error($sMessage, 'DeadLock', $e->getMessage());
+		IssueLog::Error($sMessage, LogChannels::DEADLOCK, $e->getMessage());
 	}
 
 	/**
@@ -855,7 +873,7 @@ class CMDBSource
 		$oKPI = new ExecutionKPI();
 		try
 		{
-			$oResult = self::$m_oMysqli->query($sSql);
+			$oResult = self::GetMySQLiForQuery()->query($sSql);
 		}
 		catch(mysqli_sql_exception $e)
 		{
@@ -895,7 +913,7 @@ class CMDBSource
 		$oKPI = new ExecutionKPI();
 		try
 		{
-			$oResult = self::$m_oMysqli->query($sSql);
+			$oResult = self::GetMySQLiForQuery()->query($sSql);
 		}
 		catch(mysqli_sql_exception $e)
 		{
@@ -977,7 +995,7 @@ class CMDBSource
 	{
 		try
 		{
-			$oResult = self::$m_oMysqli->query($sSql);
+			$oResult = self::GetMySQLiForQuery()->query($sSql);
 		}
 		catch(mysqli_sql_exception $e)
 		{
@@ -1465,7 +1483,7 @@ class CMDBSource
 		$sSql = "SELECT * FROM `$sTable`";
 		try
 		{
-			$oResult = self::$m_oMysqli->query($sSql);
+			$oResult = self::GetMySQLiForQuery()->query($sSql);
 		}
 		catch(mysqli_sql_exception $e)
 		{
diff --git a/core/dbobject.class.php b/core/dbobject.class.php
index 9a49a4bad..222e63205 100644
--- a/core/dbobject.class.php
+++ b/core/dbobject.class.php
@@ -3271,13 +3271,6 @@ abstract class DBObject implements iDisplay
 					$this->DBWriteLinks();
 					$this->WriteExternalAttributes();
 
-					// following lines are resetting changes (so after this {@see DBObject::ListChanges()} won't return changes anymore)
-					// new values are already in the object (call {@see DBObject::Get()} to get them)
-					// call {@see DBObject::ListPreviousValuesForUpdatedAttributes()} to get changed fields and previous values
-					$this->m_bDirty = false;
-					$this->m_aTouchedAtt = array();
-					$this->m_aModifiedAtt = array();
-
 					if (count($aChanges) != 0)
 					{
 						$this->RecordAttChanges($aChanges, $aOriginalValues);
diff --git a/core/inlineimage.class.inc.php b/core/inlineimage.class.inc.php
index 8dc78d89f..583b5c4b8 100644
--- a/core/inlineimage.class.inc.php
+++ b/core/inlineimage.class.inc.php
@@ -198,31 +198,29 @@ class InlineImage extends DBObject
 			$sOQL = 'SELECT InlineImage WHERE temp_id = :temp_id';
 			$oSearch = DBObjectSearch::FromOQL($sOQL);
 			$oSet = new DBObjectSet($oSearch, array(), array('temp_id' => $sTempId));
-            $aInlineImagesId = array();
-			while($oInlineImage = $oSet->Fetch())
-			{
-                $aInlineImagesId[] = $oInlineImage->GetKey();
+			$aInlineImagesId = array();
+			while ($oInlineImage = $oSet->Fetch()) {
+				$aInlineImagesId[] = $oInlineImage->GetKey();
 				$oInlineImage->SetItem($oObject);
 				$oInlineImage->Set('temp_id', '');
 				$oInlineImage->DBUpdate();
 			}
-            IssueLog::Trace('FinalizeInlineImages (see $aInlineImagesId for the id list)', 'InlineImage', array(
-                '$sObjectClass' => get_class($oObject),
-                '$sTransactionId' => $iTransactionId,
-                '$sTempId' => $sTempId,
-                '$aInlineImagesId' => $aInlineImagesId,
-                '$sUser' => UserRights::GetUser(),
-                'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-            ));
+			IssueLog::Trace('FinalizeInlineImages (see $aInlineImagesId for the id list)', LogChannels::INLINE_IMAGE, array(
+				'$sObjectClass' => get_class($oObject),
+				'$sTransactionId' => $iTransactionId,
+				'$sTempId' => $sTempId,
+				'$aInlineImagesId' => $aInlineImagesId,
+				'$sUser' => UserRights::GetUser(),
+				'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+			));
 		}
-        else
-        {
-            IssueLog::Trace('FinalizeInlineImages "error" $iTransactionId is null', 'InlineImage', array(
-                '$sObjectClass' => get_class($oObject),
-                '$sTransactionId' => $iTransactionId,
-                '$sUser' => UserRights::GetUser(),
-                'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-            ));
+        else {
+	        IssueLog::Trace('FinalizeInlineImages "error" $iTransactionId is null', LogChannels::INLINE_IMAGE, array(
+		        '$sObjectClass' => get_class($oObject),
+		        '$sTransactionId' => $iTransactionId,
+		        '$sUser' => UserRights::GetUser(),
+		        'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+	        ));
         }
 	}
 
@@ -253,12 +251,12 @@ class InlineImage extends DBObject
             $aInlineImagesId[] = $oInlineImage->GetKey();
 			$oInlineImage->DBDelete();
 		}
-        IssueLog::Trace('OnFormCancel', 'InlineImage', array(
-            '$sTempId' => $sTempId,
-            '$aInlineImagesId' => $aInlineImagesId,
-            '$sUser' => UserRights::GetUser(),
-            'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-        ));
+		IssueLog::Trace('OnFormCancel', LogChannels::INLINE_IMAGE, array(
+			'$sTempId' => $sTempId,
+			'$aInlineImagesId' => $aInlineImagesId,
+			'$sUser' => UserRights::GetUser(),
+			'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+		));
 	}
 
 	/**
@@ -608,17 +606,17 @@ JS
 	 */
     protected function AfterInsert()
     {
-        IssueLog::Trace(__METHOD__, 'InlineImage', array(
-            'id' => $this->GetKey(),
-            'expire' => $this->Get('expire'),
-            'temp_id' => $this->Get('temp_id'),
-            'item_class' => $this->Get('item_class'),
-            'item_id' => $this->Get('item_id'),
-            'item_org_id' => $this->Get('item_org_id'),
-            'secret' => $this->Get('secret'),
-            'user' => $sUser = UserRights::GetUser(),
-            'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-            'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
+	    IssueLog::Trace(__METHOD__, LogChannels::INLINE_IMAGE, array(
+		    'id' => $this->GetKey(),
+		    'expire' => $this->Get('expire'),
+		    'temp_id' => $this->Get('temp_id'),
+		    'item_class' => $this->Get('item_class'),
+		    'item_id' => $this->Get('item_id'),
+		    'item_org_id' => $this->Get('item_org_id'),
+		    'secret' => $this->Get('secret'),
+		    'user' => $sUser = UserRights::GetUser(),
+		    'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+		    'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
         ));
 
 	    parent::AfterInsert();
@@ -629,17 +627,17 @@ JS
 	 */
     protected function AfterUpdate()
     {
-        IssueLog::Trace(__METHOD__, 'InlineImage', array(
-            'id' => $this->GetKey(),
-            'expire' => $this->Get('expire'),
-            'temp_id' => $this->Get('temp_id'),
-            'item_class' => $this->Get('item_class'),
-            'item_id' => $this->Get('item_id'),
-            'item_org_id' => $this->Get('item_org_id'),
-            'secret' => $this->Get('secret'),
-            'user' => $sUser = UserRights::GetUser(),
-            'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-            'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
+	    IssueLog::Trace(__METHOD__, LogChannels::INLINE_IMAGE, array(
+		    'id' => $this->GetKey(),
+		    'expire' => $this->Get('expire'),
+		    'temp_id' => $this->Get('temp_id'),
+		    'item_class' => $this->Get('item_class'),
+		    'item_id' => $this->Get('item_id'),
+		    'item_org_id' => $this->Get('item_org_id'),
+		    'secret' => $this->Get('secret'),
+		    'user' => $sUser = UserRights::GetUser(),
+		    'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+		    'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
         ));
 
 	    parent::AfterUpdate();
@@ -650,17 +648,17 @@ JS
 	 */
 	protected function AfterDelete()
     {
-        IssueLog::Trace(__METHOD__, 'InlineImage', array(
-            'id' => $this->GetKey(),
-            'expire' => $this->Get('expire'),
-            'temp_id' => $this->Get('temp_id'),
-            'item_class' => $this->Get('item_class'),
-            'item_id' => $this->Get('item_id'),
-            'item_org_id' => $this->Get('item_org_id'),
-            'secret' => $this->Get('secret'),
-            'user' => $sUser = UserRights::GetUser(),
-            'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-            'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
+	    IssueLog::Trace(__METHOD__, LogChannels::INLINE_IMAGE, array(
+		    'id' => $this->GetKey(),
+		    'expire' => $this->Get('expire'),
+		    'temp_id' => $this->Get('temp_id'),
+		    'item_class' => $this->Get('item_class'),
+		    'item_id' => $this->Get('item_id'),
+		    'item_org_id' => $this->Get('item_org_id'),
+		    'secret' => $this->Get('secret'),
+		    'user' => $sUser = UserRights::GetUser(),
+		    'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+		    'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
         ));
 
 	    parent::AfterDelete();
diff --git a/core/log.class.inc.php b/core/log.class.inc.php
index 147a82044..a8b94091f 100644
--- a/core/log.class.inc.php
+++ b/core/log.class.inc.php
@@ -518,12 +518,9 @@ class FileLog
 		{
 			flock($hLogFile, LOCK_EX);
 			$sDate = date('Y-m-d H:i:s');
-			if (empty($aContext))
-			{
+			if (empty($aContext)) {
 				fwrite($hLogFile, "$sDate | $sText\n");
-			}
-			else
-			{
+			} else {
 				$sContext = var_export($aContext, true);
 				fwrite($hLogFile, "$sDate | $sText\n$sContext\n");
 			}
@@ -534,6 +531,21 @@ class FileLog
 	}
 }
 
+
+/**
+ * Simple enum like class to factorize channels values as constants
+ * Channels are used especially as parameters in {@see \LogAPI} methods
+ *
+ * @since 2.7.5 3.0.0 N°4012
+ */
+class LogChannels
+{
+	const DEADLOCK = 'DeadLock';
+	const INLINE_IMAGE = 'InlineImage';
+	const PORTAL = 'portal';
+}
+
+
 abstract class LogAPI
 {
 	public const CHANNEL_DEFAULT = '';
@@ -546,6 +558,7 @@ abstract class LogAPI
 	public const LEVEL_TRACE = 'Trace';
 	/**
 	 * @var string default log level
+	 * @see GetMinLogLevel
 	 * @used-by GetLevelDefault
 	 * @since 2.7.1 N°2977
 	 */
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php b/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
index 474f26b8c..ce48aed3c 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
@@ -31,6 +31,7 @@ use DBObjectSet;
 use DBSearch;
 use FieldExpression;
 use IssueLog;
+use LogChannels;
 use MetaModel;
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Request;
@@ -441,9 +442,9 @@ class BrowseBrickController extends BrickController
 			}
 		}
 
-		IssueLog::Debug('Portal BrowseBrick query', 'portal', array(
-			'portalId' => $sPortalId,
-			'brickId' => $sBrickId,
+		IssueLog::Debug('Portal BrowseBrick query', LogChannels::PORTAL, array(
+			'sPortalId' => $sPortalId,
+			'sBrickId' => $sBrickId,
 			'oql' => $oSet->GetFilter()->ToOQL(),
 		));
 
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php b/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
index dfc1a59e1..28853bfc2 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
@@ -44,6 +44,7 @@ use FieldExpression;
 use iPopupMenuExtension;
 use IssueLog;
 use JSButtonItem;
+use LogChannels;
 use MetaModel;
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Request;
@@ -816,10 +817,10 @@ class ManageBrickController extends BrickController
 				);
 			}
 
-			IssueLog::Debug('Portal ManageBrick query', 'portal', array(
-				'portalId' => $sPortalId,
-				'brickId' => $sBrickId,
-				'groupingTab' => $sGroupingTab,
+			IssueLog::Debug('Portal ManageBrick query', LogChannels::PORTAL, array(
+				'sPortalId' => $sPortalId,
+				'sBrickId' => $sBrickId,
+				'sGroupingTab' => $sGroupingTab,
 				'oql' => $oSet->GetFilter()->ToOQL(),
 				'aGroupingTabs' => $aGroupingTabs,
 			));
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
index 043ad462f..fe20324fb 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
@@ -78,6 +78,12 @@ class ObjectFormManager extends FormManager
 	protected $aFormProperties;
 	/** @var array $aCallbackUrls */
 	protected $aCallbackUrls = array();
+	/**
+	 * List of hidden fields, used for form update (eg. remove them from the form regarding they dependencies)
+	 * @var array $aHiddenFieldsId
+	 * @since 2.7.5
+	 */
+	protected $aHiddenFieldsId = array();
 
 	/**
 	 * Creates an instance of \Combodo\iTop\Portal\Form\ObjectFormManager from JSON data that must contain at least :
@@ -954,6 +960,8 @@ class ObjectFormManager extends FormManager
 			if($oField->GetHidden() === false)
 			{
 				$oForm->AddField($oField);
+			} else {
+				$this->aHiddenFieldsId[]=$oField->GetId();
 			}
 		}
 
@@ -1485,4 +1493,22 @@ class ObjectFormManager extends FormManager
 		}
 		return $oChangeOp;
 	}
+
+	/**
+	 * @return array
+	 * @since 2.7.5
+	 */
+	public function GetHiddenFieldsId()
+	{
+		return $this->aHiddenFieldsId;
+	}
+
+	/**
+	 * @param array $aHiddenFieldsId
+	 * @since 2.7.5
+	 */
+	public function SetHiddenFieldsId($aHiddenFieldsId)
+	{
+		$this->aHiddenFieldsId = $aHiddenFieldsId;
+	}
 }
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php b/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
index 1e4deb3b9..f3cebbe03 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Helper/ObjectFormHandlerHelper.php
@@ -280,8 +280,8 @@ class ObjectFormHandlerHelper
 				->SetFormProperties($aFormProperties);
 
 			$oFormManager->Build();
-
-			// Check the number of editable fields
+			$aFormData['hidden_fields'] = $oFormManager->GetHiddenFieldsId();
+				// Check the number of editable fields
 			$aFormData['editable_fields_count'] = $oFormManager->GetForm()->GetEditableFieldCount();
 		}
 		else
@@ -388,6 +388,7 @@ class ObjectFormHandlerHelper
 		$aFormData['object_state'] = $oFormManager->GetObject()->GetState();
 		$aFormData['fieldset'] = $aFieldSetData;
 		$aFormData['display_mode'] = (isset($aFormProperties['properties'])) ? $aFormProperties['properties']['display_mode'] : ApplicationHelper::FORM_DEFAULT_DISPLAY_MODE;
+		$aFormData['hidden_fields'] = $oFormManager->GetHiddenFieldsId();
 		// - Set a text to be copied on title if the object is not in creation
 		if($sMode !== static::ENUM_MODE_CREATE && !empty($sObjectId))
 		{
diff --git a/js/form_handler.js b/js/form_handler.js
index c3eff5c67..c709c5e43 100644
--- a/js/form_handler.js
+++ b/js/form_handler.js
@@ -151,9 +151,16 @@ $(function()
 		// Intended for overloading in derived classes
 		_onUpdateSuccess: function(oData, sFormPath)
 		{
+			var me = this;
+			if(oData.form.hidden_fields !== undefined)
+			{
+				$.each(oData.form.hidden_fields, function( index, value ) {
+					me.element.find('[data-form-path="' + sFormPath + '"][data-field-id="'+value+'"][data-attribute-flag-hidden="false"]').children().remove();
+				});
+			}
 			if(oData.form.updated_fields !== undefined)
 			{
-				this.element.find('[data-form-path="' + sFormPath + '"]').trigger('update_form', {updated_fields: oData.form.updated_fields});
+				me.element.find('[data-form-path="' + sFormPath + '"]').trigger('update_form', {updated_fields: oData.form.updated_fields});
 			}
 		},
 		// Intended for overloading in derived classes
diff --git a/pages/ajax.render.php b/pages/ajax.render.php
index 578158e19..871fc77e5 100644
--- a/pages/ajax.render.php
+++ b/pages/ajax.render.php
@@ -2491,15 +2491,15 @@ EOF
 							$aResult['height'] = $aDimensions['height'];
 						}
 
-                        IssueLog::Trace('InlineImage created', 'InlineImage', array(
-                            '$operation' => $operation,
-                            '$aResult' => $aResult,
-                            'secret' => $oAttachment->Get('secret'),
-                            'temp_id' => $sTempId,
-                            'item_class' => $sObjClass,
-                            'user' => UserRights::GetUser(),
-                            'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-                            'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
+                        IssueLog::Trace('InlineImage created', LogChannels::INLINE_IMAGE, array(
+	                        '$operation' => $operation,
+	                        '$aResult' => $aResult,
+	                        'secret' => $oAttachment->Get('secret'),
+	                        'temp_id' => $sTempId,
+	                        'item_class' => $sObjClass,
+	                        'user' => UserRights::GetUser(),
+	                        'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+	                        'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
                         ));
 					}
 					else
@@ -2542,15 +2542,15 @@ EOF
 					$oAttachment->Set('secret', sprintf('%06x', mt_rand(0, 0xFFFFFF))); // something not easy to guess
 					$iAttId = $oAttachment->DBInsert();
 
-                    IssueLog::Trace('InlineImage created', 'InlineImage', array(
-                        '$operation' => $operation,
-                        'secret' => $oAttachment->Get('secret'),
-                        'temp_id' => $sTempId,
-                        'item_class' => $sObjClass,
-                        'user' => UserRights::GetUser(),
-                        'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
-                        'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
-                    ));
+					IssueLog::Trace('InlineImage created', LogChannels::INLINE_IMAGE, array(
+						'$operation' => $operation,
+						'secret' => $oAttachment->Get('secret'),
+						'temp_id' => $sTempId,
+						'item_class' => $sObjClass,
+						'user' => UserRights::GetUser(),
+						'HTTP_REFERER' => @$_SERVER['HTTP_REFERER'],
+						'REQUEST_URI' => @$_SERVER['REQUEST_URI'],
+					));
 				}
 
 			} catch (FileUploadException $e)
diff --git a/setup/compiler.class.inc.php b/setup/compiler.class.inc.php
index 21e284cd1..1fe4a515b 100644
--- a/setup/compiler.class.inc.php
+++ b/setup/compiler.class.inc.php
@@ -64,6 +64,14 @@ class MFCompiler
 	/** @var \ThemeHandlerService */
 	protected static $oThemeHandlerService;
 
+	/**
+	 * Path to the "calculate hKeys" file
+	 * If this file is present, then we don't recalculate hkeys
+	 *
+	 * @var string
+	 */
+	public const REBUILD_HKEYS_NEVER= APPROOT.'data/.setup-rebuild-hkeys-never';
+
 	/** @var \ModelFactory */
 	protected $oFactory;
 
@@ -167,6 +175,20 @@ class MFCompiler
 		unlink(static::USE_SYMBOLIC_LINKS_FILE_PATH);
 	}
 
+	/**
+	 * @return bool possible return values :
+	 *   * if flag is present true, false otherwise
+	 *
+	 * @uses \file_exists()
+	 * @uses REBUILD_HKEYS_NEVER
+	 *
+	 * @since 2.7.5
+	 */
+	public static function SkipRebuildHKeys(): bool
+	{
+		return (file_exists(static::REBUILD_HKEYS_NEVER));
+	}
+
 	/**
 	 * Compile the data model into PHP files and data structures
 	 *
diff --git a/setup/runtimeenv.class.inc.php b/setup/runtimeenv.class.inc.php
index 5f9023857..988a9bf1d 100644
--- a/setup/runtimeenv.class.inc.php
+++ b/setup/runtimeenv.class.inc.php
@@ -598,11 +598,16 @@ class RunTimeEnvironment
 				$this->log_ok("Database structure successfully updated.");
 	
 				// Check (and update only if it seems needed) the hierarchical keys
-				ob_start();
-				MetaModel::CheckHKeys(false /* bDiagnosticsOnly */, true /* bVerbose*/, true /* bForceUpdate */); // Since in 1.2-beta the detection was buggy, let's force the rebuilding of HKeys
-				$sFeedback = ob_get_clean();
-				$this->log_ok("Hierchical keys rebuilt: $sFeedback");
-	
+				if (MFCompiler::SkipRebuildHKeys()) {
+					$this->log_ok("Hierchical keys are NOT rebuilt due to the presence of the \"data/.setup-rebuild-hkeys-never\" file");
+				} else {
+					ob_start();
+					$this->log_ok("Start of rebuilt of hierchical keys. If you have problems with this step, you can skip it by creating a \".setup-rebuild-hkeys-never\" file in data");
+					MetaModel::CheckHKeys(false /* bDiagnosticsOnly */, true /* bVerbose*/, true /* bForceUpdate */); // Since in 1.2-beta the detection was buggy, let's force the rebuilding of HKeys
+					$sFeedback = ob_get_clean();
+					$this->log_ok("Hierchical keys rebuilt: $sFeedback");
+				}
+
 				// Check (and fix) data sync configuration
 				ob_start();
 				MetaModel::CheckDataSources(false /*$bDiagnostics*/, true/*$bVerbose*/);
diff --git a/test/core/CMDBSourceTest.php b/test/core/CMDBSource/CMDBSourceTest.php
similarity index 93%
rename from test/core/CMDBSourceTest.php
rename to test/core/CMDBSource/CMDBSourceTest.php
index 229db18b5..a787c0316 100644
--- a/test/core/CMDBSourceTest.php
+++ b/test/core/CMDBSource/CMDBSourceTest.php
@@ -113,11 +113,6 @@ class CMDBSourceTest extends ItopTestCase
 				"ENUM('value 1 (with parenthesis)','value 2') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",
 				"enum('value 1 (with parenthesis)','value 3') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",
 			),
-			'ENUM with different values, containing parenthesis' => array(
-				false,
-				"ENUM('value 1 ) with parenthesis)','value 2') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",
-				"enum('value 1 (with parenthesis)','value 3') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",
-			),
 		);
 	}
 }
diff --git a/test/core/CMDBSource/DeadLockInjection.php b/test/core/CMDBSource/DeadLockInjection.php
new file mode 100644
index 000000000..12aa2e4c6
--- /dev/null
+++ b/test/core/CMDBSource/DeadLockInjection.php
@@ -0,0 +1,63 @@
+<?php
+/**
+ * @copyright   Copyright (C) 2010-2021 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+
+namespace Combodo\iTop\Test\UnitTest\Core;
+
+
+use CMDBSource;
+use Exception;
+use IssueLog;
+use MySQLException;
+use utils;
+
+class DeadLockInjection
+{
+	private $bMustFail = false;
+	private $iRequestCount = 0;
+	private $iFailAt = 0;
+	private $bShowRequest = true;
+
+	/**
+	 *
+	 * @param int $iFailAt
+	 */
+	public function SetFailAt($iFailAt)
+	{
+		$this->bMustFail = true;
+		$this->iRequestCount = 0;
+		$this->iFailAt = $iFailAt;
+		$this->bShowRequest = true;
+	}
+
+	/**
+	 * @param bool $bShowRequest
+	 */
+	public function SetShowRequest($bShowRequest)
+	{
+		$this->bShowRequest = $bShowRequest;
+	}
+
+
+	public function query($sSQL)
+	{
+		if (utils::StartsWith($sSQL, "SELECT")) {
+			return;
+		}
+		if ($this->bShowRequest) {
+			$sShortSQL = substr(preg_replace("/\s+/", " ", substr($sSQL, 0, 180)), 0, 150);
+			echo "$sShortSQL\n";
+		}
+		if (CMDBSource::IsInsideTransaction() && $this->bMustFail) {
+			$this->iRequestCount++;
+			if ($this->iRequestCount == $this->iFailAt) {
+				echo "Generating a FAKE DEADLOCK\n";
+				IssueLog::Trace("Generating a FAKE DEADLOCK", 'cmdbsource');
+				throw new MySQLException("FAKE DEADLOCK", [], new Exception("FAKE DEADLOCK", 1213));
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/test/core/CMDBSource/TransactionsTest.php b/test/core/CMDBSource/TransactionsTest.php
new file mode 100644
index 000000000..4c07226d4
--- /dev/null
+++ b/test/core/CMDBSource/TransactionsTest.php
@@ -0,0 +1,248 @@
+<?php
+/**
+ * @copyright   Copyright (C) 2010-2021 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Test\UnitTest\Core;
+
+use CMDBSource;
+use Combodo\iTop\Test\UnitTest\ItopTestCase;
+use Exception;
+use MetaModel;
+
+/**
+ *
+ * @group itopRequestMgmt
+ * Class TransactionsTest
+ *
+ * @package Combodo\iTop\Test\UnitTest\Core
+ */
+class TransactionsTest extends ItopTestCase
+{
+	/** @var DeadLockInjection */
+	private $oMySQLiMock;
+
+	protected function setUp()
+	{
+		parent::setUp();
+		require_once ('DeadLockInjection.php');
+		require_once(APPROOT.'/core/cmdbsource.class.inc.php');
+		$sEnv = 'production';
+		$sConfigFile = APPCONF.$sEnv.'/config-itop.php';
+
+		MetaModel::Startup($sConfigFile, false, true, false, $sEnv);
+
+		$oInitialMysqli = CMDBSource::GetMysqli();
+		$this->oMySQLiMock = new DeadLockInjection();
+
+		$oMockMysqli = $this->getMockBuilder('mysqli')
+			->setMethods(['query'])
+			->getMock();
+		$oMockMysqli->expects($this->any())
+			->method('query')
+			->will($this->returnCallback(
+				function ($sSql) use ($oInitialMysqli) {
+					$this->oMySQLiMock->query($sSql);
+					return $oInitialMysqli->query($sSql);
+				}
+			));
+
+		$this->InvokeNonPublicStaticMethod('CMDBSource', 'SetMySQLiForQuery', [$oMockMysqli]);
+	}
+
+	/**
+	 * Test DBInsertNoReload database transaction by provoking deadlock exceptions
+	 *
+	 * @dataProvider DBInsertProvider
+	 *
+	 * @param int $iFailAt  Specify the request occurrence that fails
+	 * @param bool $bIsInDB Indicates if the object must have been created or not
+	 *
+	 * @throws \ArchivedObjectException
+	 * @throws \CoreCannotSaveObjectException
+	 * @throws \CoreException
+	 * @throws \CoreUnexpectedValue
+	 * @throws \DeleteException
+	 * @throws \MySQLException
+	 * @throws \MySQLHasGoneAwayException
+	 * @throws \OQLException
+	 */
+	public function testDBInsert($iFailAt, $bIsInDB)
+	{
+		// Create a UserRequest with 2 contacts
+		$oTicket = MetaModel::NewObject('UserRequest', [
+			'ref' => 'Test Ticket',
+			'title' => 'Create OK',
+			'description' => 'Create OK',
+			'caller_id' => 15,
+			'org_id' => 3,
+		]);
+		$oLinkSet = $oTicket->Get('contacts_list');
+		$oLinkSet->AddItem(MetaModel::NewObject('lnkContactToTicket', ['contact_id' => 6]));
+		$oLinkSet->AddItem(MetaModel::NewObject('lnkContactToTicket', ['contact_id' => 7]));
+
+		$this->oMySQLiMock->SetFailAt($iFailAt);
+		$this->debug("---> DBInsert()");
+		try {
+			$oTicket->DBWrite();
+		}
+		catch (Exception $e) {
+			// If an exception occurs must be a deadlock
+			$this->assertTrue(CMDBSource::IsDeadlockException($e), $e->getMessage());
+		}
+
+		// Verify if the ticket is considered as saved in the database
+		$this->assertEquals($bIsInDB, !$oTicket->IsNew());
+
+		if (!$oTicket->IsNew()) {
+			$this->oMySQLiMock->SetShowRequest(false);
+			// Delete created objects
+			$oTicket->DBDelete();
+		}
+	}
+
+	public function DBInsertProvider()
+	{
+		return [
+			"Normal case" => ['iFailAt' => -1, 'bIsInDB' => true],
+			"ticket" => ['iFailAt' => 1, 'bIsInDB' => false],
+			"ticket_request" => ['iFailAt' => 2, 'bIsInDB' => false],
+			"priv_change" => ['iFailAt' => 3, 'bIsInDB' => false],
+			"priv_changeop" => ['iFailAt' => 4, 'bIsInDB' => false],
+			"priv_changeop_create" => ['iFailAt' => 5, 'bIsInDB' => false],
+			"History 4" => ['iFailAt' => 6, 'bIsInDB' => false],
+			"History 5" => ['iFailAt' => 7, 'bIsInDB' => false],
+			"History 6" => ['iFailAt' => 8, 'bIsInDB' => false],
+			"History 7" => ['iFailAt' => 9, 'bIsInDB' => false],
+			"History 8" => ['iFailAt' => 10, 'bIsInDB' => false],
+			"History 9" => ['iFailAt' => 11, 'bIsInDB' => false],
+			"History 10" => ['iFailAt' => 12, 'bIsInDB' => false],
+			"History 11" => ['iFailAt' => 13, 'bIsInDB' => false],
+			"History 12" => ['iFailAt' => 14, 'bIsInDB' => false],
+			"History 13" => ['iFailAt' => 15, 'bIsInDB' => false],
+			"History 14" => ['iFailAt' => 16, 'bIsInDB' => false],
+			"History 15" => ['iFailAt' => 17, 'bIsInDB' => false],
+			// For 3.0 when CRUD sequence is ok
+//			"History 16" => ['iFailAt' => 18, 'bIsInDB' => false],
+//			"History 17" => ['iFailAt' => 19, 'bIsInDB' => false],
+//			"History 18" => ['iFailAt' => 20, 'bIsInDB' => false],
+//			"History 19" => ['iFailAt' => 21, 'bIsInDB' => false],
+//			"History 20" => ['iFailAt' => 22, 'bIsInDB' => false],
+//			"History 21" => ['iFailAt' => 23, 'bIsInDB' => false],
+//			"History 22" => ['iFailAt' => 24, 'bIsInDB' => false],
+//			"History 23" => ['iFailAt' => 25, 'bIsInDB' => false],
+//			"History 24" => ['iFailAt' => 26, 'bIsInDB' => false],
+//			"History 25" => ['iFailAt' => 27, 'bIsInDB' => false],
+//			"History 26" => ['iFailAt' => 28, 'bIsInDB' => false],
+//			"History 27" => ['iFailAt' => 29, 'bIsInDB' => false],
+//			"History 28" => ['iFailAt' => 30, 'bIsInDB' => false],
+//			"History 29" => ['iFailAt' => 31, 'bIsInDB' => false],
+//			"History 30" => ['iFailAt' => 32, 'bIsInDB' => false],
+//			"History 31" => ['iFailAt' => 33, 'bIsInDB' => false],
+//			"History 32" => ['iFailAt' => 34, 'bIsInDB' => false],
+//			"History 33" => ['iFailAt' => 35, 'bIsInDB' => false],
+//			"History 34" => ['iFailAt' => 36, 'bIsInDB' => false],
+//			"History 35" => ['iFailAt' => 37, 'bIsInDB' => false],
+//			"History 36" => ['iFailAt' => 38, 'bIsInDB' => false],
+//			"History 37" => ['iFailAt' => 39, 'bIsInDB' => false],
+//			"History 38" => ['iFailAt' => 40, 'bIsInDB' => false],
+		];
+	}
+
+	/**
+ 	 * Test DBUpdate database transaction by provoking deadlock exceptions
+	 *
+	 * @dataProvider DBUpdateProvider
+	 * @param $iFailAt
+	 *
+	 * @throws \ArchivedObjectException
+	 * @throws \CoreCannotSaveObjectException
+	 * @throws \CoreException
+	 * @throws \CoreUnexpectedValue
+	 * @throws \DeleteException
+	 * @throws \MySQLException
+	 * @throws \MySQLHasGoneAwayException
+	 * @throws \OQLException
+	 */
+	public function testDBUpdate($iFailAt, $bIsModified)
+	{
+		// Create a UserRequest into the database with 2 contacts
+		$oTicket = MetaModel::NewObject('UserRequest', [
+			'ref' => 'Test Ticket',
+			'title' => 'Create OK',
+			'description' => 'Create OK',
+			'solution' => 'Create OK',
+			'caller_id' => 15,
+			'org_id' => 3,
+		]);
+		$oLinkSet = $oTicket->Get('contacts_list');
+		$oLinkSet->AddItem(MetaModel::NewObject('lnkContactToTicket', ['contact_id' => 6]));
+		$oLinkSet->AddItem(MetaModel::NewObject('lnkContactToTicket', ['contact_id' => 7]));
+		//$oTicket->Set('contacts_list', $oLinkSet);
+
+		$this->oMySQLiMock->SetShowRequest(false);
+		$oTicket->DBWrite();
+
+		// Verify that the object is considered as saved in the database
+		$this->assertEquals(true, !$oTicket->IsNew());
+
+		// Reload from db
+		$oTicket = MetaModel::GetObject('UserRequest', $oTicket->GetKey());
+		$oTicket->Set('description', 'Update OK');
+		$oTicket->Set('solution', 'Test OK');
+		$oLinkSet = $oTicket->Get('contacts_list');
+		$oLinkSet->AddItem(MetaModel::NewObject('lnkContactToTicket', ['contact_id' => 8]));
+		$oTicket->Set('contacts_list', $oLinkSet);
+
+		// Provoke an error during the update
+		$this->oMySQLiMock->SetFailAt($iFailAt);
+		$this->debug("---> DBUpdate()");
+		try {
+			$oTicket->DBWrite();
+		}
+		catch (Exception $e) {
+			// If an exception occurs must be a deadlock
+			$this->assertTrue(CMDBSource::IsDeadlockException($e));
+		}
+
+		// Verify if the ticket is considered as saved in the database
+		$this->assertEquals($bIsModified, $oTicket->IsModified());
+
+		// Reload from db after the update to check the value present in the database
+		$oTicket = MetaModel::GetObject('UserRequest', $oTicket->GetKey());
+		if ($bIsModified) {
+			$this->assertEquals('Create OK', $oTicket->Get('solution'));
+		} else {
+			$this->assertEquals('Test OK', $oTicket->Get('solution'));
+		}
+
+		if (!$oTicket->IsNew()) {
+			$this->oMySQLiMock->SetShowRequest(false);
+			// Delete created objects
+			$oTicket->DBDelete();
+		}
+	}
+
+	public function DBUpdateProvider()
+	{
+		return [
+			"Normal case" => ['iFailAt' => -1, 'bIsModified' => false],
+			"ticket_request" => ['iFailAt' => 1, 'bIsModified' => true],
+			"lnkcontacttoticket" => ['iFailAt' => 2, 'bIsModified' => true],
+			"History 1" => ['iFailAt' => 3, 'bIsModified' => true],
+			"History 2" => ['iFailAt' => 4, 'bIsModified' => true],
+			"History 3" => ['iFailAt' => 5, 'bIsModified' => true],
+			"History 4" => ['iFailAt' => 6, 'bIsModified' => true],
+			"History 5" => ['iFailAt' => 7, 'bIsModified' => true],
+			"History 6" => ['iFailAt' => 8, 'bIsModified' => true],
+			"History 7" => ['iFailAt' => 9, 'bIsModified' => true],
+			"History 8" => ['iFailAt' => 10, 'bIsModified' => true],
+			"History 9" => ['iFailAt' => 11, 'bIsModified' => true],
+			"History 10" => ['iFailAt' => 12, 'bIsModified' => true],
+			"History 11" => ['iFailAt' => 13, 'bIsModified' => true],
+			"History 12" => ['iFailAt' => 14, 'bIsModified' => true],
+			"History 13" => ['iFailAt' => 15, 'bIsModified' => true],
+		];
+	}
+}
\ No newline at end of file