php exec() - mysqldump creates an empty file

Question

I want to create a backup from a database, but I get only a blank file.

include(\'config.php\');

$command = \"mysqldump --opt -h \".$_host.\" -u \".$_user.\         


        

Answer 1

For those on Macs

I was battling this issue the entire evening today. Silly mistake: one needs to chmod the directory that you are dumping the file to.

I ran this which fixed the issue:

chmod -R 777 your_dump_directory/

Answer 2

Take the variables out of the quotes and remove --opt.

Also make sure that you are having unique file names

$backupfile = $dbname . date("Y-m-d-H-i-s") . '.sql';

$command = "D:\xampp\mysql\bin\mysqldump -u $_user -p$_pass $_db > $backupfile";

system($command);

Answer 3

These are the parameters

-uROOT -pPASSWORD --databases DB --result-file=FILE.SQL

Answer 4

If you look at the manual for exec the output goes to an array that is the second argument. That may be the source of the problem.

Answer 5

You should remove the space between the -p and the password.

--opt isn't needed with recent versions of mysql.

Other than that, your syntax is correct so if it doesn't work with the -p fix, you should check the parameters and the produced command.

Answer 6

Try this one:

$command = 'd:\xampp\mysql\bin\mysqldump --opt -u '.$_user.' -p'.$_pass.' '.$_db.' > test.sql 2>&1';

-its about permission issue.