How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?

Question

I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do:

SELECT column1, column2
INTO OUTFILE 'outfile.csv'
FIELDS TERMINATED BY ','
FROM table_name;

outfile.csv will be created on the server in the same directory this database's files are stored in.

However, when I change my query to:

SELECT column1, column2
INTO OUTFILE '/data/outfile.csv'
FIELDS TERMINATED BY ','
FROM table_name;

I get:

ERROR 1 (HY000): Can't create/write to file '/data/outfile.csv' (Errcode: 13)

Errcode 13 is a permissions error, but I get it even if I change ownership of /data to mysql:mysql and give it 777 permissions. MySQL is running as user "mysql".

Strangely I can create the file in /tmp, just not in any other directory I've tried, even with permissions set such that user mysql should be able to write to the directory.

This is MySQL 5.0.75 running on Ubuntu.

Answer 1

You need to provide an absolute path, not a relative path.

Provide the full path to the /data directory you are trying to write to.

Answer 2

I know you said that you tried already setting permissions to 777, but as I have an evidence that for me it was a permission issue I'm posting what I exactly run hoping it can help. Here is my experience:

tmp $ pwd
/Users/username/tmp
tmp $ mkdir bkptest
tmp $ mysqldump -u root -T bkptest bkptest
mysqldump: Got error: 1: Can't create/write to file '/Users/username/tmp/bkptest/people.txt' (Errcode: 13) when executing 'SELECT INTO OUTFILE'
tmp $ chmod a+rwx bkptest/
tmp $ mysqldump -u root -T bkptest bkptest
tmp $ ls bkptest/
people.sql  people.txt
tmp $ 

Answer 3

Some things to try:

• is the secure_file_priv system variable set? If it is, all files must be written to that directory.
• ensure that the file does not exist - MySQL will only create new files, not overwrite existing ones.

Answer 4

Which particular version of Ubuntu is this and is this Ubuntu Server Edition?

Recent Ubuntu Server Editions (such as 10.04) ship with AppArmor and MySQL's profile might be in enforcing mode by default. You can check this by executing sudo aa-status like so:

# sudo aa-status
5 profiles are loaded.
5 profiles are in enforce mode.
   /usr/lib/connman/scripts/dhclient-script
   /sbin/dhclient3
   /usr/sbin/tcpdump
   /usr/lib/NetworkManager/nm-dhcp-client.action
   /usr/sbin/mysqld
0 profiles are in complain mode.
1 processes have profiles defined.
1 processes are in enforce mode :
   /usr/sbin/mysqld (1089)
0 processes are in complain mode.

If mysqld is included in enforce mode, then it is the one probably denying the write. Entries would also be written in /var/log/messages when AppArmor blocks the writes/accesses. What you can do is edit /etc/apparmor.d/usr.sbin.mysqld and add /data/ and /data/* near the bottom like so:

...
/usr/sbin/mysqld {
    ...
    /var/log/mysql/ r,
    /var/log/mysql/* rw,
    /var/run/mysqld/mysqld.pid w,
    /var/run/mysqld/mysqld.sock w,
    /data/ r,
    /data/* rw,
}

And then make AppArmor reload the profiles.

# sudo /etc/init.d/apparmor reload

Answer 5

Does Ubuntu use SELinux? Check to see if it's enabled and enforcing. /var/log/audit/audit.log may be helpul (if that's where Ubuntu sticks it -- that's the RHEL/Fedora location).

Answer 6

Ubuntu uses AppArmor and that is whats preventing you from accessing /data/. Fedora uses selinux and that would prevent this on a RHEL/Fedora/CentOS machine.

To modify AppArmor to allow MySQL to access /data/ do the follow:

sudo gedit /etc/apparmor.d/usr.sbin.mysqld

add this line anywhere in the list of directories:

/data/ rw,

then do a :

sudo /etc/init.d/apparmor restart

Another option is to disable AppArmor for mysql altogether, this is NOT RECOMMENDED:

sudo mv /etc/apparmor.d/usr.sbin.mysqld /etc/apparmor.d/disable/

Don't forget to restart apparmor:

sudo /etc/init.d/apparmor restart