MySQL may be writing the file into its own data directory, like /var/lib/mysql/<databasename>
for example. To specify the path, use a full path.
However, it must be a directory that is writable by the user account the MySQL server daemon is running under. For that reason, I'll often use /tmp
:
Specify the path you want to write to as in:
INTO OUTFILE '/tmp/mydata.csv'
And note that MySQL will write the file on the MySQL server, not on your client machine. Therefore remote connections will create output files on the remote server. See also SELECT INTO OUTFILE local ? for more details and workarounds.
Systemd & Linux
A note about writing to /tmp
on a Linux system running systemd
:
Some years after originally posting this, I found myself unable to locate a file written to /tmp
via
...INTO OUTFILE '/tmp/outfile.csv'
on a MariaDB 5.5 server running Fedora Linux with systemd
. Instead of writing the file directly to /tmp/outfile.csv
as specified, that directory and file were created beneath a systemd directory in /tmp
:
/tmp/systemd-mariadb.service-XXXXXXX/tmp/outfile.csv
While the file outfile.csv
itself and the tmp/
subdirectory were both created world-writable, the systemd service directory itself has 700 permissions and is root-owned, requiring sudo
access to retrieve the file within it.
Rather than specifying the absolute path in MariaDB as /tmp/outfile.csv
and specifying it relatively as outfile.csv
, the file was written as expected into MariaDB's data directory for the currently selected database.
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