Read/insert Chinese data from mysql database saved by php code - php

Question

I want to use ruby to read/insert data to a mysql database, onto which data were saved by a php code. When I read Chinese data, it does not appear correctly. It appears like 刘佳. But in a php page, it shows Chinese data correctly as 刘佳.
I confirmed the database uses utf-8 charset (CHARSET=utf8 COLLATE=utf8_unicode_ci).
my ruby code
require 'active_record'
class Student < ActiveRecord::Base
end
ActiveRecord::Base.establish_connection(
adapter: 'mysql2',
host: 'xxxx',
username: 'xxxx',
password: 'xxxx',
database: 'xxx_db',
encoding: 'utf8'
)
puts Student.first.name
It outputs an unknown string "刘佳".
How can I read Chinese data correctly and save a new Chinese record to database?

Answer 1

puts Student.first.name
It outputs an unknown string "刘佳".
I believe that is because whatever device you are using to view the ruby program's output (a terminal window?) is not set to "UTF-8" (see below for how to check that).
As far as I can tell, you have done everything right:
mysql docs:(http://dev.mysql.com/doc/refman/5.0/en/charset-applications.html)
Specify character settings per database. To create a database such
that its tables will use a given default character set and collation
for data storage, use a CREATE DATABASE statement like this:
CREATE DATABASE mydb
DEFAULT CHARACTER SET utf8
DEFAULT COLLATE utf8_general_ci;
Tables created in the database will use utf8 and utf8_general_ci by
default for any character columns.
Applications that use the database should also configure their
connection to the server each time they connect. This can be done by
executing a SET NAMES 'utf8' statement after connecting. The statement
can be used regardless of connection method: The mysql client, PHP
scripts, and so forth.
rails docs: (http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/MysqlAdapter.html)
All the options for ActiveRecord::Base.establish_connection() are as follows (note the description for :encoding):
Options:
:host - Defaults to “localhost”.
:port - Defaults to 3306.
:socket - Defaults to “/tmp/mysql.sock”.
:username - Defaults to “root”
:password - Defaults to nothing.
:database - The name of the database. No default, must be provided.
:encoding - (Optional) Sets the client encoding by executing
“SET NAMES <encoding>” after connection.
:reconnect - Defaults to false (See MySQL documentation: dev.mysql.com/doc/refman/5.0/en/auto-reconnect.html).
:strict - Defaults to true. Enable STRICT_ALL_TABLES. (See MySQL documentation: dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html)
:variables - (Optional) A hash session variables to send as `SET ##SESSION.key = value` on each database connection. Use the value `:default` to set a variable to its DEFAULT value. (See MySQL documentation: dev.mysql.com/doc/refman/5.0/en/set-statement.html).
:sslca - Necessary to use MySQL with an SSL connection.
:sslkey - Necessary to use MySQL with an SSL connection.
:sslcert - Necessary to use MySQL with an SSL connection.
:sslcapath - Necessary to use MySQL with an SSL connection.
:sslcipher - Necessary to use MySQL with an SSL connection.
(I had a hard time locating those, so I am posting all of them for future google searchers.)
And, when I run the following program in a terminal window, e.g.:
$ r 1.rb
where my terminal window is set to UTF-8:
~/ruby_programs$ locale
LANG="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_CTYPE="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_ALL=
...
# encoding: UTF-8
require 'active_record'
require 'mysql2'
class Student < ActiveRecord::Base
end
ActiveRecord::Base.establish_connection(
adapter: 'mysql2',
#host: 'localhost', #this is the default
#username: 'root', #this is the default
#password: '', #this is the default
database: 'mydb2',
encoding: 'utf8'
)
#Insert a record in the db (It shouldn't matter whether a php or a ruby program writes to the database.)
Student.create(
name: "\u732a", #Because of the comment at top of the program, this
#string will be encoded in UTF-8
info: "a pig" #..so will this one.
)
name = Student.first.name
puts name
name.each_byte{|b| printf "%x \n", b}
puts
...the output I see is a Chinese character in my terminal window, which when compared to the Chinese character for 'pig' matches exactly, followed by:
e7
8c
aa
And if you look here: http://www.fileformat.info/info/unicode/char/732a/index.html, those bytes make up the UTF-8 encoding of the unicode integer \u732a, which represents 'pig' in Chinese, which is what was in the string that was inserted into the db.
In any case, you should run my program and if you get the same kind of error, then it will prove that it is your terminal's encoding that is the problem.