用select into outfile拒绝php / mysql访问

I have the following php code:

我有以下PHP代码:

<?php

$hostname="db.";
$database="db..";
$username="db...";
$password="pw...";
$mysql = mysql_connect($hostname, $username, $password);

if(!$mysql) 
 echo 'Not conneted to the database...' . mysql_error() ;
else
 echo 'Connected to the database...' ;

// select the appropriate database
$mysqldb = mysql_select_db( $database );
if(!$mysqldb) 
 die('Could not select the database...'  . mysql_error());
else
 echo '<br /><br />Connected to database...<br /><br />' ;

$chk_table_access = 'select * from table_name where 1';
$chk_access = mysql_query($chk_table_access);
echo $chk_table_access . '<br /><br />';
if (!$chk_access) 
 echo 'Could not access table: ' . mysql_error() ;
else
 echo 'Table was accessed..<br /><br />' ;

$backup = 'SELECT * INTO OUTFILE "result.csv" FIELDS TERMINATED BY "," OPTIONALLY     ENCLOSED BY ';
$backup = $backup . "'" . '"' . "'" ;
$backup = $backup . ' FROM cities WHERE 1';
echo $backup . '<br /><br />';
$bk_success = mysql_query($backup);
if (!$bk_success)
 echo 'The backup was not successful. Reason: '  . mysql_error();
?>
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