diff --git a/libraries/export/xml.php b/libraries/export/xml.php
index e55c52b1d..5b82ad5ec 100644
--- a/libraries/export/xml.php
+++ b/libraries/export/xml.php
@@ -84,8 +84,8 @@ function PMA_exportHeader() {
     global $table;
     global $tables;
     
-    $export_struct = $GLOBALS[$what . '_export_struc'];
-    $export_data = $GLOBALS[$what . '_export_contents'];
+    $export_struct = isset($GLOBALS[$what . '_export_struc']) ? true : false;
+    $export_data = isset($GLOBALS[$what . '_export_contents']) ? true : false;
 
     if ($GLOBALS['output_charset_conversion']) {
         $charset = $GLOBALS['charset_of_file'];
@@ -139,11 +139,11 @@ function PMA_exportHeader() {
                 $type = 'table';
             }
             
-            if ($is_view && !$GLOBALS[$what . '_export_views']) {
+            if ($is_view && ! isset($GLOBALS[$what . '_export_views'])) {
                 continue;
             }
             
-            if (!$is_view && !$GLOBALS[$what . '_export_tables']) {
+            if (! $is_view && ! isset($GLOBALS[$what . '_export_tables'])) {
                 continue;
             }
             
@@ -155,7 +155,7 @@ function PMA_exportHeader() {
             $head .= $tbl . ';' . $crlf;
             $head .= '            </pma:' . $type . '>' . $crlf;
             
-            if ($GLOBALS[$what . '_export_triggers']) {
+            if (isset($GLOBALS[$what . '_export_triggers']) && $GLOBALS[$what . '_export_triggers']) {
                 // Export triggers
                 $triggers = PMA_DBI_get_triggers($db, $table);
                 if ($triggers) {
@@ -178,7 +178,7 @@ function PMA_exportHeader() {
             }
         }
         
-        if ($GLOBALS[$what . '_export_functions']) {
+        if (isset($GLOBALS[$what . '_export_functions']) && $GLOBALS[$what . '_export_functions']) {
             // Export functions
             $functions = PMA_DBI_get_procedures_or_functions($db, 'FUNCTION');
             if ($functions) {
@@ -201,7 +201,7 @@ function PMA_exportHeader() {
             }
         }
         
-        if ($GLOBALS[$what . '_export_procedures']) {
+        if (isset($GLOBALS[$what . '_export_procedures']) && $GLOBALS[$what . '_export_procedures']) {
             // Export procedures
             $procedures = PMA_DBI_get_procedures_or_functions($db, 'PROCEDURE');
             if ($procedures) {
@@ -250,8 +250,7 @@ function PMA_exportDBHeader($db) {
     global $crlf;
     global $what;
     
-    if ($GLOBALS[$what . '_export_contents'])
-    {
+    if (isset($GLOBALS[$what . '_export_contents']) && $GLOBALS[$what . '_export_contents']) {
         $head = '    <!--' . $crlf
               . '    - ' . $GLOBALS['strDatabase'] . ': ' . (isset($GLOBALS['use_backquotes']) ? PMA_backquote($db) : '\'' . $db . '\''). $crlf
               . '    -->' . $crlf
@@ -278,8 +277,7 @@ function PMA_exportDBFooter($db) {
     global $crlf;
     global $what;
     
-    if ($GLOBALS[$what . '_export_contents'])
-    {
+    if (isset($GLOBALS[$what . '_export_contents']) && $GLOBALS[$what . '_export_contents']) {
         return PMA_exportOutputHandler('    </database>' . $crlf);
     }
     else
@@ -318,8 +316,7 @@ function PMA_exportDBCreate($db) {
 function PMA_exportData($db, $table, $crlf, $error_url, $sql_query) {
     global $what;
     
-    if ($GLOBALS[$what . '_export_contents'])
-    {
+    if (isset($GLOBALS[$what . '_export_contents']) && $GLOBALS[$what . '_export_contents']) {
         $result      = PMA_DBI_query($sql_query, null, PMA_DBI_QUERY_UNBUFFERED);
         
         $columns_cnt = PMA_DBI_num_fields($result);