diff --git a/include/lib/database_core.class.php b/include/lib/database_core.class.php
index 165a0aec4..6cd6f30f2 100644
--- a/include/lib/database_core.class.php
+++ b/include/lib/database_core.class.php
@@ -969,9 +969,11 @@ class DatabaseCore
 
     /**
      * @brief with the handle of a successull query, echo each row into CSV and
-     * send it directly
-     * @param type $ret handle to a query
-     * @param type $aheader double array, each item of the array contains
+     * send it directly to output. To save it into a file, it is needed to send first the HEADER as CSV. If there are
+     *less column than column defined in $aheader, then the columns not included in the header are not displaid
+     *
+     * @param handle  $ret handle to a query
+     * @param array $aheader double array, each item of the array contains (idx : title, type)
      * a key type (num) and a key title
      */
     function query_to_csv($ret, $aheader)
@@ -990,6 +992,7 @@ class DatabaseCore
             // for each rows, for each value
             $e=0;
             foreach ($row as $row_item){
+                if ( $e >= count($a_header)) break;
                 switch ($aheader[$e]['type']) {
                     case 'num':
                         $csv->add($row_item, "number");
diff --git a/unit-test/include/lib/databaseCore.Test.php b/unit-test/include/lib/databaseCoreTest.php
similarity index 50%
rename from unit-test/include/lib/databaseCore.Test.php
rename to unit-test/include/lib/databaseCoreTest.php
index 370f29a45..246097350 100644
--- a/unit-test/include/lib/databaseCore.Test.php
+++ b/unit-test/include/lib/databaseCoreTest.php
@@ -69,6 +69,61 @@ class DatabaseCoreTest extends TestCase
         
     }
 
+    /**
+     * @brief test the Query_to_CSV function
+     * @testDox  query_to_csv
+     * @return void
+     */
+    public function testQuery_to_csv()
+    {
+        $aheader=array();
+        $aheader[]=array("title"=>"date","type"=>"date");
+        $aheader[]=array("title"=>"Montant","type"=>"num");
+        $aheader[]=array("title"=>"Label","type"=>"string");
+
+        $ret=$this->object->exec_sql("select j_id,j_montant,j_text from jrnx where coalesce(j_text ,'') != '' order by j_id limit 10");
+        ob_start();
+        $this->object->query_to_csv($ret, $aheader);
+        $p_content=ob_get_contents();
+        ob_end_clean();
+        $filename=__FUNCTION__."_result.txt";
+        \Noalyss\Facility::save_file(__DIR__, $filename, $p_content);
+        $this->assertFileExists(__DIR__."/$filename");
+        $filesize=filesize(__DIR__."/$filename");
+        $this->assertEquals(284, $filesize,"$filename has not 284 bytes");
+        $this->assertStringContainsString("Documentation", $p_content,"$filename invalid content");
+
+    }
+    /**
+     * @brief test the Query_to_CSV function
+     * @testDox  query_to_csv
+     * @return void
+     */
+    public function testQuery_to_csvSmallHeader()
+    {
+        $aheader=array();
+        $aheader[]=array("title"=>"date","type"=>"date");
+        $aheader[]=array("title"=>"Montant","type"=>"num");
+        $aheader[]=array("title"=>"Label","type"=>"string");
+
+        $ret=$this->object->exec_sql("
+                    select j_id,j_montant,j_text,j_poste 
+                    from 
+                        jrnx 
+                    where 
+                        coalesce(j_text ,'') != '' order by j_id limit 10");
+        ob_start();
+        $this->object->query_to_csv($ret, $aheader);
+        $p_content=ob_get_contents();
+        ob_end_clean();
+        $filename=__FUNCTION__."_result.txt";
+        \Noalyss\Facility::save_file(__DIR__, $filename, $p_content);
+        $this->assertFileExists(__DIR__."/$filename");
+        $filesize=filesize(__DIR__."/$filename");
+        $this->assertEquals(284, $filesize,"$filename has not 284 bytes");
+        $this->assertStringContainsString("Documentation", $p_content,"$filename invalid content");
+
+    }
     
 
 }
\ No newline at end of file