Unicode support in RailsEdit

As of Rails 1.2 (see here) Unicode support is included right out of the box.

Set up a brand new application with a simple scaffold and check the HTML output returned by the browser; it will include a line like this:

<meta http-equiv="content-type" content="text/html;charset=UTF-8" />

Likewise, the actual HTTP headers returned to the browser will be appropriately set. You can test this out using curl:

curl -i http://example.com/rails_app

Note the charset=utf-8 in the returned header:

HTTP/1.1 200 OK
Cache-Control: no-cache
Connection: Keep-Alive
Date: Mon, 02 Apr 2007 19:10:27 GMT
Content-Type: text/html; charset=utf-8
Server: WEBrick/1.3.1 (Ruby/1.8.6/2007-03-13)
Content-Length: 1317

But there is one extra thing you have to do to complete the configuration; in your config/database.yml file add a line like this for each MySQL database:

encoding: utf8

Note that as of Rails 2.0 this configuration is included by default in the database.yml file.


Although Rails itself is (almost) set-up to use UTF-8 out of the box MySQL is not necessarily the same. The default character set is ISO 8859-1, otherwise known as Latin-1.

Confirming this, I installed the latest version from the 4.1 series on my Mac OS X box (see "Installing MySQL 4.1.22 (binary) on Mac OS X 10.4.9") and on performing a SHOW CREATE TABLE example_table; the table information included the following:


InnoDB tables are fairly nice, offering transactions, row-level locking, and foreign-key constraints (see http://dev.mysql.com/doc/refman/4.1/en/innodb-overview.html), but the charset value is not what we want. I have seen some posts that claim that InnoDB tables don’t support full-text searching if UTF-8 is used, but the MySQL documentation clarifies this further stating that full-text searching is not support in InnoDB tables with any encoding at all.

Database creation time

In theory, you can set the default charset at the moment you create the database. Instead of:

mysqladmin -u root create application_name_development

You would do this:

mysqladmin -u root create application_name_development --default-character-set=utf8

But in practice this didn’t work for me. The setting is apparently ignored.

The alternative approach described here is to create the database from inside the MySQL shell:

$ mysql -u root
mysql> CREATE DATABASE application_name_development CHARACTER SET 'UTF8';

The same thing, from the command line:

mysql -u root -e "CREATE DATABASE application_name_development CHARACTER SET 'UTF8';"

Unlike the other method, this one does seem to work (see "Finding out the encoding of a MySQL database"):

mysql> USE application_name_development;
Database changed
mysql> SHOW VARIABLES LIKE 'character\_set\_%';
| Variable_name            | Value  |
| character_set_client     | latin1 |
| character_set_connection | latin1 |
| character_set_database   | utf8   |
| character_set_results    | latin1 |
| character_set_server     | latin1 |
| character_set_system     | utf8   |
6 rows in set (0.00 sec)

To start a MySQL session and issue the CREATE DATABASE command in a single operation you can do:

mysql -u root -e "CREATE DATABASE application_name_development CHARACTER SET 'UTF8';"

Yet another way, when working with Rails, is to use Rake tasks; assuming you have your database.yml file correctly configured then you can just:

rake db:create:all

Across all databases on the server

The same post explains how, if you control the entire MySQL server, you can set the following in your /etc/mysql/my.cnf file:

character-set-server = utf8

default-character-set = utf8

If you do this then all databases will be automatically created using UTF-8 as the default character set. There is no need to pass any special command line options or to manually pass the CHARACTER SET parameter when creating a database.

Although this is convenient, it may not be possible for all users and it may also cause compatibility issues with other software which might incorrectly assume that the database is running with Latin-1 text encoding; as such my preferred method is to create new databases from within the MySQL shell as described above.

Migration time

If you cannot set this at the database level you can also do it from inside your migrations. Modify your migrations from:

create_table :examples do |t|


create_table :examples, :options => 'default charset=utf8' do |t|

Then your tables will have the appropriate charsets regardless of the database settings.

External links