SQLite error 'attempt to write a readonly database' during insert?

Solution 1:

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.

Solution 2:

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?

Solution 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

Solution 4:

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

Solution 5:

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 :)

Edit:

If you can't set environment variables you can use one of the other methods listed here: https://www.sqlite.org/tempfiles.html#temporary_file_storage_locations like PRAGMA temp_store_directory = 'directory-name';