diff --git a/dev/initdemo/initdemo.sql b/dev/initdemo/initdemo.sql
index 32515ac6c27..d89a0a9b6e8 100644
--- a/dev/initdemo/initdemo.sql
+++ b/dev/initdemo/initdemo.sql
@@ -2412,13 +2412,13 @@ SET @saved_cs_client     = @@character_set_client;
 SET character_set_client = utf8;
 CREATE TABLE `llx_element_element` (
   `rowid` int(11) NOT NULL auto_increment,
-  `sourceid` int(11) NOT NULL default '0',
+  `fk_source` int(11) NOT NULL default '0',
   `sourcetype` varchar(16) NOT NULL default '',
-  `targetid` int(11) NOT NULL default '0',
+  `fk_target` int(11) NOT NULL default '0',
   `targettype` varchar(16) NOT NULL default '',
   PRIMARY KEY  (`rowid`),
-  UNIQUE KEY `idx_element_element_idx1` (`sourceid`,`sourcetype`,`targetid`,`targettype`),
-  KEY `idx_element_element_targetid` (`targetid`)
+  UNIQUE KEY `idx_element_element_idx1` (`fk_source`,`sourcetype`,`fk_target`,`targettype`),
+  KEY `idx_element_element_fk_target` (`fk_target`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
 SET character_set_client = @saved_cs_client;
 
diff --git a/doc/dev/dbmodel/dolibarr_schema.mwb b/doc/dev/dbmodel/dolibarr_schema.mwb
index ac0b0950fc2..badb7842c17 100644
Binary files a/doc/dev/dbmodel/dolibarr_schema.mwb and b/doc/dev/dbmodel/dolibarr_schema.mwb differ
diff --git a/htdocs/commonobject.class.php b/htdocs/commonobject.class.php
index 56f96481ec8..0c5a64a3cd8 100644
--- a/htdocs/commonobject.class.php
+++ b/htdocs/commonobject.class.php
@@ -832,6 +832,19 @@ class CommonObject
 			return -1;
 		}
 	}
+	
+	/**
+	 * 	Add objects linked in llx_element_element.
+	 */
+	function add_object_linked($sourceid,$sourcetype,$targetid,$targettype)
+	{
+		$sql = "INSERT INTO ".MAIN_DB_PREFIX."element_element (";
+		$sql.= "fk_source";
+		$sql.= ", sourcetype";
+		$sql.= ", fk_target";
+		$sql.= ", targettype";
+		$sql.= ") VALUES (";
+	}
 
 	/**
 	 * 	Load array of objects linked to current object. Links are loaded into this->linked_object array.
@@ -841,10 +854,11 @@ class CommonObject
 		$this->linked_object=array();
 
 		// Links beetween objects are stored in this table
-		$sql = 'SELECT sourceid, sourcetype, targetid, targettype';
+		$sql = 'SELECT fk_source, sourcetype, fk_target, targettype';
 		$sql.= ' FROM '.MAIN_DB_PREFIX.'element_element';
-		$sql.= " WHERE (sourceid = '".$this->id."' AND sourcetype = 'invoice')";
-		$sql.= " OR    (targetid = '".$this->id."' AND targettype = 'invoice')";
+		$sql.= " WHERE (fk_source = '".$this->id."' AND sourcetype = 'invoice')";
+		$sql.= " OR    (fk_target = '".$this->id."' AND targettype = 'invoice')";
+		
 		dol_syslog("CommonObject::load_object_linked sql=".$sql);
 		$resql = $this->db->query($sql);
 		if ($resql)
@@ -854,13 +868,13 @@ class CommonObject
 			while ($i < $num)
 			{
 				$obj = $this->db->fetch_object($resql);
-				if ($obj->sourceid == $this->id)
+				if ($obj->fk_source == $this->id)
 				{
-					$this->linked_object[]=array('linkid'=>$obj->targetid, 'type'=>$obj->targettype);
+					$this->linked_object[]=array('linkid'=>$obj->fk_target, 'type'=>$obj->targettype);
 				}
-				if ($obj->targetid == $this->id)
+				if ($obj->fk_target == $this->id)
 				{
-					$this->linked_object[]=array('linkid'=>$obj->sourceid, 'type'=>$obj->sourcetype);
+					$this->linked_object[]=array('linkid'=>$obj->fk_source, 'type'=>$obj->sourcetype);
 				}
 				$i++;
 			}
diff --git a/htdocs/install/mysql/migration/2.7.0-2.8.0.sql b/htdocs/install/mysql/migration/2.7.0-2.8.0.sql
index c6d162d6414..1f2504d79d8 100755
--- a/htdocs/install/mysql/migration/2.7.0-2.8.0.sql
+++ b/htdocs/install/mysql/migration/2.7.0-2.8.0.sql
@@ -14,3 +14,10 @@ ALTER TABLE llx_stock_mouvement ADD COLUMN label varchar(128);
 
 ALTER TABLE llx_deplacement ADD COLUMN ref varchar(30) DEFAULT NULL AFTER rowid;
 ALTER TABLE llx_deplacement ADD COLUMN entity integer DEFAULT 1 NOT NULL AFTER ref;
+
+ALTER TABLE llx_element_element DROP INDEX idx_element_element_idx1;
+ALTER TABLE llx_element_element DROP INDEX idx_element_element_targetid;
+ALTER TABLE llx_element_element CHANGE sourceid fk_source integer NOT NULL;
+ALTER TABLE llx_element_element CHANGE targetid fk_target integer NOT NULL;
+ALTER TABLE llx_element_element ADD UNIQUE INDEX idx_element_element_idx1 (fk_source, sourcetype, fk_target, targettype);
+ALTER TABLE llx_element_element ADD INDEX idx_element_element_fk_target (fk_target);
diff --git a/htdocs/install/mysql/tables/llx_element_element.key.sql b/htdocs/install/mysql/tables/llx_element_element.key.sql
index d065c0f2136..e1b82141ea1 100644
--- a/htdocs/install/mysql/tables/llx_element_element.key.sql
+++ b/htdocs/install/mysql/tables/llx_element_element.key.sql
@@ -19,10 +19,10 @@
 -- ============================================================================
 
 
-ALTER TABLE llx_element_element ADD UNIQUE INDEX idx_element_element_idx1 (sourceid, sourcetype, targetid, targettype);
+ALTER TABLE llx_element_element ADD UNIQUE INDEX idx_element_element_idx1 (fk_source, sourcetype, fk_target, targettype);
 
 	
-ALTER TABLE llx_element_element ADD INDEX idx_element_element_targetid (targetid);
+ALTER TABLE llx_element_element ADD INDEX idx_element_element_fk_target (fk_target);
 
--- Pas de contraite sur sourceid et targetid car pointe sur differentes tables
+-- Pas de contraite sur fk_source et fk_target car pointe sur differentes tables
 	
\ No newline at end of file
diff --git a/htdocs/install/mysql/tables/llx_element_element.sql b/htdocs/install/mysql/tables/llx_element_element.sql
index 53823a62793..3ec5983b008 100644
--- a/htdocs/install/mysql/tables/llx_element_element.sql
+++ b/htdocs/install/mysql/tables/llx_element_element.sql
@@ -24,9 +24,9 @@
 create table llx_element_element
 (
   rowid           	integer AUTO_INCREMENT PRIMARY KEY,  
-  sourceid			integer NOT NULL,
+  fk_source			integer NOT NULL,
   sourcetype		varchar(16) NOT NULL,
-  targetid			integer NOT NULL,
+  fk_target			integer NOT NULL,
   targettype		varchar(16) NOT NULL
 ) type=innodb;
 
diff --git a/htdocs/livraison/livraison.class.php b/htdocs/livraison/livraison.class.php
index b903c1b9589..a4a97eb5d3f 100644
--- a/htdocs/livraison/livraison.class.php
+++ b/htdocs/livraison/livraison.class.php
@@ -388,7 +388,7 @@ class Livraison extends CommonObject
 					$resql=$this->db->query($sql);
 					if ($resql)
 					{
-						// Si module stock g�r� et que expedition faite depuis un entrepot
+						// Si module stock gere et que expedition faite depuis un entrepot
 						if (!$conf->expedition->enabled && $conf->stock->enabled && $this->entrepot_id && $conf->global->STOCK_CALCULATE_ON_SHIPMENT == 1)
 						{