php - MySQL SELECT .... INTO OUTFILE not working -

i have used following code backup mysql table:

$query = "select * outfile '/tmp/mytabledb.txt' mytable"; 

it not appear working.

the following error checking code used:

$result = mysql_query($query); if ($result)     echo 'database backed up'; else     echo 'not backed up'; 

but documentation not clear whether or not return value generated.

the message 'not backed up' echoed.

the database accessed via wampserver on windows machine.

the manual located at:

http://dev.mysql.com/doc/refman/5.0/en/select-into.html

does not appear cover issue.

has come across problem & found solution while using wampserver?

be sure database user has file permission.

grant file on db.* user;  

a quote manual posted:

the file created on server host, must have file privilege use syntax.