How to pull mysql database from heroku to local machine - mysql

Question

Hi I have a ruby on rails app hosted on heroku and it is using mysql as database.
Now I have to take backup of the database to my local machine. But I am getting issues while taking backup.
For this I installed taps gem and I am using following commands for it
heroku pg:pull mysql2://username#hostname.cleardb.com/heroku_database local_database --app my_app
but it is giving error as !Your app has no databases.
Can any one guide me how to pull mysql database from heroku to local machine.
EDIT
I have used following syntax for the command
heroku pg:pull <REMOTE_SOURCE_DATABASE> <LOCAL_TARGET_DATABASE>
and for getting REMOTE_SOURCE_DATABASE I have used following command
heroku config:get DATABASE_URL --app my_app
I refer this link1 and link2 for more detailed heroku documentation.

Answer 1

The pg:pull command only works with Postgres databases in your Heroku app. But, you are using a third-party MySQL provider. Your database is hosted on the ClearDB servers and it's available to anyone with the right credentials, including both your app server on Heroku and your dev machine.
Even though there aren't special commands to pull the database, you don't need any - plain mysqldump should do.
mysqldump -h hostname.cleardb.com -u username heroku_database | mysql local_database

Answer 2

Running $heroku config | grep ^DATABASE will give you something like this:
DATABASE_URL: mysql2://username:password#host/dbname?reconnect=true`
From there you can construct your db dump command:
mysqldump -h host -p -u username dbname | mysql local_database
This will prompt you for the password which you received from the previous command. If you wanted to create a script that would automatically include the password from the heroku command you could do something like this:
mysqldump -u username --password=`heroku config | grep ^DATABASE | sed 's/.*[a-z0-9][a-z0-9]*:\([a-z][a-z0-9]*\).*/\1/'` -h host dbname | mysql cedric
In this way you can have a script that will import the database without requiring any user input but also does not expose the password to your database.

Answer 3

(IMPORTANT DISCLAIMER: You MUST have your database.yml configured correctly in order for this to work. I am not responsible for any data you lose as a result of running the below script.)
For Ruby on Rails users ... you could consider writing a Rake task like these db:clone tasks below.
I find myself using this script constantly to clone down from production to development. It's way easier than remembering the mysqldump syntax, much less all of the usernames and passwords involved ...
To clone from production to development:
rake db:clone:production
To clone from staging to development:
rake db:clone:staging
To clone from production to staging:
rake db:clone:production_to_staging
And here's the code enjoy (and be careful in setting up your database.yml):
namespace :db do
namespace :clone do
class << self
%w(development test staging production).each do |env|
define_method("#{env}_db") do
Rails.configuration.database_configuration[env]
end
end
end
def clone_db(from_db, to_db)
start_time = Time.now
puts "Cloning Remote DB...."
system("mysqldump -h#{from_db['host']} -u#{from_db['username']} -p#{from_db['password']} #{from_db['database']} | mysql #{to_db['database']} -u#{to_db['username']} -p#{to_db['password']}")
puts "Import Successful"
end_time = Time.now
puts "===================="
puts "Job Completed: #{end_time - start_time} Seconds"
end
task :staging => :environment do
clone_db(staging_db, development_db)
end
task :production => :environment do
clone_db(production_db, development_db)
end
task :production_to_staging => :environment do
clone_db(production_db, staging_db) if Rails.env.staging?
end
end
end