php substr sorunu

 
  	 $ogr=mysql_query("select * from ogrenci_veli where tc='$tc' && rol_id='5'");  
  	 $ogr_id=mysql_result($ogr,0,'id'); 
  	  
  	 $date=mysql_query("select * from devam where ogrenci_id='$ogr_id'"); 
  	$date1=mysql_result($date,0,'tarih'); 
  	//echo $date1; 
  	  $gun= substr($date1['tarih'], 8); 
  	  $ay= substr($date1['tarih'], 5, 2); 
  	 $yil= substr($date1['tarih'], 0, 4);  
  	  
  	  echo $yil; 
  	  echo $ay;