diff --git a/htdocs/accountancy/class/bookkeeping.class.php b/htdocs/accountancy/class/bookkeeping.class.php
index ee3188da125..a72dfbe238e 100644
--- a/htdocs/accountancy/class/bookkeeping.class.php
+++ b/htdocs/accountancy/class/bookkeeping.class.php
@@ -330,20 +330,20 @@ class BookKeeping extends CommonObject
 				$sql .= ",'" . $this->db->escape($this->doc_ref) . "'";
 				$sql .= "," . $this->fk_doc;
 				$sql .= "," . $this->fk_docdet;
-				$sql .= ",'" . $this->db->escape($this->thirdparty_code) . "'";
-				$sql .= ",'" . $this->db->escape($this->subledger_account) . "'";
-				$sql .= ",'" . $this->db->escape($this->subledger_label) . "'";
+				$sql .= "," . (!empty($this->thirdparty_code)?("'".$this->db->escape($this->thirdparty_code)."'"):"NULL");
+				$sql .= "," . (!empty($this->subledger_account)?("'".$this->db->escape($this->subledger_account)."'"):"NULL");
+				$sql .= "," . (!empty($this->subledger_label)?("'".$this->db->escape($this->subledger_label)."'"):"NULL");
 				$sql .= ",'" . $this->db->escape($this->numero_compte) . "'";
 				$sql .= ",'" . $this->db->escape($this->label_compte) . "'";
-				$sql .= ",'" . $this->db->escape($this->label_operation) . "'";
+				$sql .= "," . (!empty($this->label_operation)?("'".$this->db->escape($this->label_operation)."'"):"NULL");
 				$sql .= "," . $this->debit;
 				$sql .= "," . $this->credit;
 				$sql .= "," . $this->montant;
-				$sql .= ",'" . $this->db->escape($this->sens) . "'";
+				$sql .= "," . (!empty($this->sens)?("'".$this->db->escape($this->sens)."'"):"NULL");
 				$sql .= ",'" . $this->db->escape($this->fk_user_author) . "'";
-				$sql .= ",'".$this->db->idate($now)."'";
+				$sql .= ",'" . $this->db->idate($now)."'";
 				$sql .= ",'" . $this->db->escape($this->code_journal) . "'";
-				$sql .= ",'" . $this->db->escape($this->journal_label) . "'";
+				$sql .= "," . (!empty($this->journal_label)?("'".$this->db->escape($this->journal_label)."'"):"NULL");
 				$sql .= "," . $this->db->escape($this->piece_num);
 				$sql .= ", " . (! isset($this->entity) ? $conf->entity : $this->entity);
 				$sql .= ")";