In this article we will explain how the MariaDB and MySQL server and client library licenses affect other applications and what steps you can take to comply with the GPL or avoid having to change your applications to GPL.
In the following text we talk about MariaDB. The guidelines also apply
to MySQL in general, at least up to 5.1.55 which is the latest
stable release while writing.
<<toc>>
== Licenses used by MariaDB
MariaDB is distributed under the [[mariadb-license|GPL license]],
version 2.
The MariaDB client library is also GPL version 2, but has a
[[mariadb-license#mariadb-client-license|FLOSS exception]] that allows
you to combine it with most other open source software, without
conflicting with their license, even if that license is incompatible
with the GPL.
MySQL before 5.1.55 also had the same FLOSS exception for the C client
libraries, but the exception file and all references to it were removed
by Oracle in MySQL 5.1.55.
The [[lgpl-mysql-client-library-32358|original MySQL client library]]
was licensed under the
[[mariadb-license#mysql-lgpl-client-library|LGPL]], which allowed you
to distribute the MySQL client library freely with any application.
== Internal usage is free
The GPL license only affects code that you distribute to other parties.
Internal usage within an organization is totally free and not subject
to any conditions. There is no such thing as 'internal distribution'
that would restrict the usage of your code by requiring it to be GPLed.
Connecting to a remote service that runs MariaDB (or any other GPL
software) in the background is also free.
For internal programs for which you own all the copyright(s),
there is essentially no risk in using GPL software. The argument
you can use in your defense is that if the software became GPL
as part of the distribution, you as the copyright holder could immediately
revert your part back to its original copyright. No one has the right
to require you to reveal or redistribute your code to the outside of
your organization even if you would have distributed it internally
linked with GPL software!
If your lawyers are concerned about distributions of software linked
with GPL libraries between different legal entities within your
organization, you can solve this by distributing your components and the
GPL software separately, and have your other entity combining them.
== Distributing an application with a MariaDB connector/client
This section is for those that want to distribute the MariaDB client
library code, but not the server, with their applictions.
=== Free software/open source applications
If your application is Free software/open source and uses one of the
licenses listed in the
[[mariadb-license#mariadb-client-license|FLOSS exception]], the GPL
in the client library does not affect your application.
Note that for doing this you need to use a client that has the FLOSS
exception. This is either a MariaDB client or a MySQL client before
5.1.55.
=== Using a connector that is not GPL
If you are using a connector that is not GPL, you are only bound
by the license of that connector. Some examples are:
* [[http://php.net/manual/en/book.mysqlnd.php|MySQL native driver for PHP - mysqlnd]]
* [[http://raa.ruby-lang.org/project/ruby-mysql|ruby-mysql]]
The above have licenses that allow you to use them freely, without you
being bound by the GPL.
=== Using a database source independent framework
If you are using a framework that allows you to connect dynamically to
different RDBMS systems, any GPL
licensed module loaded by the framework will not affect the
application. Such frameworks are
* ODBC (Open Database Connectivity)
* JDBC (Java Database connectivity)
* Perl
The reason the GPL in the MySQL client library would not affect your
application in this case is that the GPL client is supporting a
standard interface and is thus merely an optional component among
many. Your application could just as easily use the framework to
connect to a RDBMS other than MariaDB or MySQL.
Any software can be connected to the GPL v2 licensed MySQL
Connector/ODBC, without the need for that software to be GPLed. This is
because there is a piece of general management software, the ODBC
manager, between the GPLed MySQL Connector/ODBC and your software. If
any logic would require the software which interfaces with MySQL
Connector/ODBC to be GPL, then that would apply also to the ODBC
manager itself. Yet, the ODBC manager is not GPL, neither on Windows
nor on Linux. By consequence, no one would be allowed to use MySQL ODBC
driver for anything.
=== Using the MariaDB C client
If you are using the MariaDB C client and you are not covered by the
[[mariadb-license#mariadb-client-license|FLOSS exception]], then you
have the following choices:
* Change your application to be GPL or to a GPL compatible license.
* Change your application to use one of the above mentioned free connectors or frameworks.
* Change to use the [[lgpl-mysql-client-library-32358|original LGPL MySQL client library]]
* Change to use the [[https://launchpad.net/libdrizzle|libdrizzle client library]].
* Support the [[http://monty-says.blogspot.com/2010/12/in-search-of-bsdlgplapache-licensed.html|effort in progress]] to create a LGPL/BSD client library.
* Buy a license from Oracle for using the MySQL client library.
* Contact [[http://skysql.com|SkySQL sales]] for another version of the MySQL client library that is not GPL.
The above applies also to MySQL up to MySQL 5.1.54. If you are using
MySQL 5.1.55 or above, you should definitely read [[licensing-faq#mysql-5155-client-license-change|this]].
== Distributing a proprietary application with the MariaDB / MySQL server
When you are distributing your application together with MariaDB or
MySQL you are bound (or can be seen to be bound by some lawyers) by
the GPL if some of the following statements apply:
* You are using GPL code from MySQL linked directly to your application. (Like the MySQL GPL client library).
* Your application requires the MariaDB server to work and without the MariaDB server it doesn't start or it has very limited functionality.
The problem with the client library can be avoided by using one of the
solutions mentioned
[[licensing-faq#distributing-an-application-with-a-mariadb-connectorclient|earlier]].
If your application works with many databases, either natively or by
using one of the
[[licensing-faq#using-a-database-source-independent-framework|database source independent frameworks]], then you can
freely distribute the MariaDB server with your application without
being affected by the GPL. The reason for this is that MariaDB
would only be an optional, independent component in your software
distribution and section 2 of the GPL explicitely allows this:
<<code>>
"In addition, mere aggregation of another work not based on
the Program with the Program (or with a work based on the Program) on
a volume of a storage or distribution medium does not bring the other
work under the scope of this License."
<</code>>
You also have the option to buy licenses for MySQL from Oracle to get
MySQL under other copyright terms. If you would like to later be able to
use MariaDB instead of MySQL, please ensure that your license
agreement allows you to make changes to the MySQL code! (This is
something that you should ensure in all cases as otherwise you may run
into bugs that Oracle will not fix, you are not allowed to fix and
could make MySQL software unusable for you!)
The rights to use the MariaDB code changes in your application can be
requested from [[http://montyprogram.com/contact|Monty Program Ab]].
== MySQL 5.1.55 client license change
In MySQL 5.1.55 Oracle removed the EXCEPTIONS-CLIENT files, which
contained the [[mariadb-license#mariadb-client-license|FLOSS
exception]] from the MySQL source code trees and the distributions.
They also removed the reference to the EXCEPTIONS-CLIENT file from all
client library code source files.
The FLOSS exception can can still (at least in February 2011) be found
on the
[[http://www.mysql.com/about/legal/licensing/foss-exception/|MySQL web
site]].
On the above web site it's clearly stated that the FLOSS exception only
applies to code that mentions the FLOSS exception in the code and if
one removes the reference, the code reverts to GPL.
To further add uncertainty for the user of MySQL 5.1.55 or later:
* The web site doesn't mention for which MySQL versions the FOSS exception
applies.
* It's not clear if one can copy the license text from the web site to include with one's applications (the current legal notice says you can't). This is something that is required with most software distributions.
* If the FLOSS exception text changes on the web site, when will it take effect?
* It's not clear for which files the FOSS exception applies (which is important if you need to compile and/or modify the client library).
From the above, one can deduce that one of the following new cases now
applies (until there is more information available):
* The default MySQL client library code is now GPL and there is no FLOSS exception anymore starting with MySQL 5.1.55.
* The MySQL client library code still has a FLOSS exception, but by having it only on the web site, Oracle can change it any time and the changes will at once affect any new distributions of the code (also for old versions of MySQL that do not include an explicit FLOSS exception in the distribution).
If you want to be safe and sure that you can continue to use the MySQL client
library with the FLOSS exception in the future without 'surprises', you
have one of the following options:
* Use the client library from MySQL 5.1.54 and never upgrade your clients to MySQL 5.1.55 or above.
* Use the MariaDB client library. This is a fork of MySQL 5.1.54 and it will not be updated with any new MySQL code to ensure we can continue to deliver it under FLOSS exception terms.
* Use some of the other MySQL client libraries or ways to connect to MySQL/MariaDB mentioned above.
== Legal notice
The text above is written by Michael "Monty" Widenius, who is not a
lawyer and you should not regard any statements of the above as
'ultimate truth' in all scenarios. On the other hand, it was David
and Monty who together decided to make MySQL GPL and also decided and
openly declared the intentions behind this license change, so there is
some merit to information in this article.
If you want a second opinion of how GPL works in this case, you can
contact [[http://www.softwarefreedom.org|Software Freedom Law Center]]
or [[http://www.fsf.org|Free Software Foundation]] about this. Neither
part has had anything to do with this KB article but they are the
default authorities to turn to when you want to know more about the
GPL.
