ต้องการเเทนที่ค่าว่าง Null ด้วยคำอื่นอ่ะคะ ต้องเขียนโค้ดประมาณไหนคะ php ต้องการความช่วยเหลือมากๆ เลยคะ

   $sqlproduct =  "SELECT t1.id_pro, t1.name_pro, t1.generation_pro, repayment_type.name_paytype, product_status.name_proS, t1.date_expPledge, product_type.name_ptype, COALESCE(product_status.name_proS, 'kk' ) 
FROM product AS t1
LEFT JOIN save_pawn ON save_pawn.id_pro = t1.id_pro
LEFT JOIN repayment_type ON repayment_type.id_paytype = t1.id_paytype
LEFT JOIN product_status ON product_status.id_proS = save_pawn.id_proS
LEFT JOIN product_type ON product_type.id_ptype = t1.id_ptype
WHERE t1.id_paytype =5
LIMIT 0 , 20"; 
		   
		 


 

		   $dataproduct=mysql_query($sqlproduct) or die(mysql_error());
		   $count = mysql_num_rows($dataproduct);


		   echo "<table width=\"780\" border = \"1\" align=\"center\"bgcolor=\"#CCFF99\" bordercolor=\"#CCCCCC\">";
		   echo"<tr bgcolor=\"#99FF33\">";
		   echo "<th  width=\"120\">รหัสสินค้า</th>";
		   echo"<th   width=\"120\"> ประเภทสินค้า</th>";
		   echo "<th  width=\"120\">ชื่อสินค้า</th>";
		   echo "<th  width=\"280\">รุ่น</th>";
		   echo "<th  width=\"180\">วันที่หลุดจำนำ</th>";
		   echo "<th  width=\"180\">สถานะสินค้า</th>";
		   echo "<th  width=\"180\">สถานะในระบบงานขาย</th>";

		   echo "<th  width=\"260\">บันทึกสินค้าขายหน้าร้าน</th>";
		   echo"</tr>";

		   
			   while ($fild=mysql_fetch_array($dataproduct))
		   {
		   		   
		   	  $id_pro =$fild[id_pro];  
			  $name_ptype = $fild[name_ptype];
			  $name_pro = $fild[name_pro];
			  $generation_pro = $fild[generation_pro]; 
			  $date_expPledge=thaidate($fild[date_expPledge]);
			 $name_paytype=$fild[name_paytype];
			$name_proS=$fild[name_proS];
		
 
	
			  echo "<tr align=\"center\">";
			  echo "<td> $id_pro</td>";
		      echo "<td align=\"left\">$name_ptype</td>";
			  echo "<td align=\"left\">$name_pro</td>";		
			  echo "<td align=\"left\">$generation_pro</td>";
  			  echo "<td>$date_expPledge</td>";
   			  echo "<td>$name_paytype</td>";
			  echo "<td>$name_proS</td>";

			  echo"<td><a href=\"productInput.php?sid=$id_pro&action=save\"> <img src=\"images/Save-icon.png\" width=\"30\" height=\"30\"></a></td>";
			echo "</tr>";
	}		 
	echo "</table>";