Added a check for NULL fields in the MySQL database backup utility
diff --git a/system/database/drivers/mysql/mysql_utility.php b/system/database/drivers/mysql/mysql_utility.php
index 0d19214..54c110e 100644
--- a/system/database/drivers/mysql/mysql_utility.php
+++ b/system/database/drivers/mysql/mysql_utility.php
@@ -218,14 +218,31 @@
 					$v = str_replace('\\\n', '\n',	$v);

 					$v = str_replace('\\\r', '\r',	$v);

 					$v = str_replace('\\\t', '\t',	$v);

-				

-					// Escape the data if it's not an integer type

-					$val_str .= ($is_int[$i] == FALSE) ? $this->db->escape($v) : $v;

-					$val_str .= ', ';

+

+					// Is the value NULL?

+					if ($v == NULL)

+					{

+						$val_str .= 'NULL';

+					}

+					else

+					{

+						// Escape the data if it's not an integer

+						if ($is_int[$i] == FALSE)

+						{

+							$val_str .= $this->db->escape($v);

+						}

+						else

+						{

+							$val_str .= $v;

+						}					

+					}					

 					

+					// Append a comma

+					$val_str .= ', ';

 					$i++;

 				}

 				

+				// Remove the comma at the end of the string

 				$val_str = preg_replace( "/, $/" , "" , $val_str);

 								

 				// Build the INSERT string

diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index eb2e3ef..d9819d4 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -73,6 +73,7 @@
     <li>Javascript Calendar plugin now uses the months and days from the calendar language file, instead of hard-coded values, internationalizing it.</li>

     <li>Removed &quot;rand()&quot; as a listed option from orderby in the <a href="./database/active_record.html">Active Record</a>, as it was MySQL only. </li>

     <li>Added titles to all user manual pages.</li>

+    <li>Added a check for NULL fields in the MySQL database backup utility.</li>

     <li>Documented the timezones() function in the <a href="./helpers/date_helper.html">Date Helper</a>.</li>

     <li>Documented unset_userdata in the <a href="./libraries/sessions.html">Session class</a>.</li>

     <li>Fixed a bug in <a href="./libraries/validation.html">Validation</a> where valid_ip() wasn't called properly</li>