SQLite: read-only database

Question

I have a SQLite database that I am using for a website. The problem is that when I try to INSERT INTO it, I get a PDOException

SQLSTATE[HY000]: General error: 8 attempt to write a readonly database

I SSH'd into the server and checked permissions, and the database has the permissions

-rw-rw-r--

I'm not that familiar with *nix permissions, but I'm pretty sure this means

• Not a directory
• Owner has read/write permissions (that's me, according to ls -l)
• Group has read/write permissions
• Everyone else only has read permissions

I also looked everywhere I knew to using the sqlite3 program, and found nothing relevant.

Because I didn't know with what permissions PDO is trying to open the database, I did

chmod o+w supplies.db

Now, I get another PDOException:

SQLSTATE[HY000]: General error: 14 unable to open database file

But it ONLY occurs when I try to execute an INSERT query after the database is open.

Any ideas on what is going on?

Answer 1

I got this error when I tried to write to a database on an Android system.

Apparently sqlite3 not only needs write permissions to the database file and the containing directory (as @austin-hyde already said in his answer) but also the environment variable TMPDIR has to point to a (possibly writable) directory.

On my Android system I set it to TMPDIR="/data/local/tmp" and now my script runs as expected :)

Answer 2

This can be caused by SELinux. If you don't want to disable SELinux completely, you need to set the db directory fcontext to httpd_sys_rw_content_t.

semanage fcontext -a -t httpd_sys_rw_content_t "/var/www/railsapp/db(/.*)?"
restorecon -v /var/www/railsapp/db

Answer 3

For me the issue was SELinux enforcement rather than permissions. The "read only database" error went away once I disabled enforcement, following the suggestion made by Steve V. in a comment on the accepted answer.

echo 0 >/selinux/enforce

Upon running this command, everything worked as intended (CentOS 6.3).

The specific issue I had encountered was during setup of Graphite. I had triple-checked that the apache user owned and could write to both my graphite.db and its parent directory. But until I "fixed" SELinux, all I got was a stack trace to the effect of: DatabaseError: attempt to write a readonly database

Answer 4

The problem, as it turns out, is that the PDO SQLite driver requires that if you are going to do a write operation (INSERT,UPDATE,DELETE,DROP, etc), then the folder the database resides in must have write permissions, as well as the actual database file.

I found this information in a comment at the very bottom of the PDO SQLite driver manual page.

Answer 5

I got the same error from IIS under windows 7. To fix this error i had to add full control permissions to IUSR account for sqlite database file. You don't need to change permissions if you use sqlite under webmatrix instead of IIS.

Answer 6

This can happen when the owner of the SQLite file itself is not the same as the user running the script. Similar errors can occur if the entire directory path (meaning each directory along the way) can't be written to.

Who owns the SQLite file? You?

Who is the script running as? Apache or Nobody?