README

This project implements two Drush commands to export and import large Drupal 7 or 8 databases faster. It does it by splitting tables into separate files and importing them afterwards in parallel.

Here is a description of each command:

• drush dumpdb dumps database tables into the temporary directory of the current environment.
• drush syncdb @example.dev downloads sql files from @example.dev and installs them in the current environment.
• drush importdb --dump-dir=/foo/bar imports all *.sql files from /foo/bar using the same method as syncdb.

There is no .module nor .info files because this is not a module. It is a Drush command. Drush can find commands in certain directories such as $HOME/.drush/ or sites/all/drush. Run drush topic docs-commands on a terminal to see other places where this project can be placed so Drush can discover it. Depending on your needs you may decide to leave this command with or without your project's versioned code.

Requirements

• Drush: version 6 or higher.
• Drupal 7 or Drupal 8.
• Database: it has been tested just on MySQL.

It highly recommended that you install GNU-parallel in the machine(s) that contain the data that you want to import. On Ubuntu, run sudo apt-get install parallel. On Mac, run brew install parallel. This is not a hard requirement, though. drush syncdb will still be able to import tables witout GNU-parallel, but it will take longer to complete.

Installation

Go to your project's root directory and run the following command:

composer require juampynr/syncdb

This will normally download the command into /path-to-drush/drush/commands/syncdb. If you want to move it somewhere within your project so it is under version control, move it to sites/all/drush or run drush dl --destination=sites/all/drush syncdb.

Next, log into the remote server which will server as the source from which the team will download tables into their local environments. Install the command there.

Usage

You should set up a periodic job that runs drush dumpdb at the remote environment that is designated as the source. This would normally be the Development environment. This can be set up through crontab or Jenkins. Here is how you can set this up in crontab:

drush @example.dev ssh
crontab -e
# Paste the following command at the bottom of the opened file:
30 2 * * * drush --root=/path/to/your/drupalroot --quiet dumpdb --structure-tables-key=common

Once this job is set up, run it once in the remote environment so it will export tables into, for example, /tmp/syncdb-tables. Now you can import these tables into your local environment with the following command:

drush syncdb @example.dev

Customizing the command

You can use the --structure-tables-key option in the same way it works for the sql-sync command. This option will export structure tables into a file called structure.sql.

If you install parallel, have a look at is options by reading the contents of the command man parallel. There could be ways for you to optimize the command even further.

Usage examples

Here are a few screenshots of a terminal session using these two commands:

Acknowledgements

• Andrew Berry (@deviantintegral) for creating MySQL Parallel where I took some of the ideas.
• Mateu Aguiló Bosh (@e0ipso) for showing me how mysql-parallel works.
• Dave Reid @davereid, for writing Concurrent Queue, from where I took the drush_invoke_concurrent() approach when GNU-parallel is not available.
• Kris Bulman (@krisbulman), for reminding me every week how slow was to download a large database.