License
SQL Relay is generally free to use and distribute, by itself, as part of a free software project, as part of a commercial system, or otherwise.
SQL Relay consists of several components, each covered by an appropriate free software license.
The SQL Relay Server is covered by the GNU GPL 2 with exceptions for specific modules and dependencies.
The command line clients are covered by the GNU GPL 2.
The client API's for C, C++, C#, Java, node.js, ODBC, PHP, Ruby and TCL API's are covered by the GNU LGPL 2.
The client API for Erlang is covered by the Creative Commons Attribtion 3.0.
The client API for Perl is covered by the Artistic License.
The PHP PDO API is covered by the PHP License 3.01.
The Python API is covered by the PointOne Public License.
Tests and documentation (except for example code in the documenation) are covered by the GNU GPL 2.
Example code given in the documenation is covered by the FSF Unlimited License.
The SQL Relay Enterprise Modules and associated license keys are covered by a commercial license.For questions, please contact licensing@firstworks.com.
GPL License Exceptions
The SQL Relay server is primarily covered by the GNU GPL, but the server is highly modular and extensible, and many of the libraries that its standard modules depend on don't meet the qualifications for linking with a GPL-licensed program. To remedy this situation, exceptions allow specific libraries to be combined with the SQL Relay server, while excluding them from the requirements of the GPL.
If you are interested in developing or distributing a module, you may need to request that a license exception be granted for the module, or the libraries that it depends on.
You do not need an exception if:
You don't distribute your module. (Eg. it is only used in house, or in a hosted application.)
or
Your module and the libraries that it depends on are released under the GPL, LGPL, or a compatible license.You do need an exception if:
You distribute your module. (Eg. freely on the internet, as part of an installation for a client, as part of a commercial product, etc.)
and
You don't want to, or are unable to release your module or libraries that it depends on under the GPL, LGPL, or a compatible license.License exceptions are generally just granted outright for modules (and their dependencies) which integrate SQL Relay with an independent system, via a client library, provided the module will be released under a free software license.
In other sitations, the terms of the license exception would depend on the details of the situation.
For questions, or to request a license exception, please contact licensing@firstworks.com.
Distribution of Modified Versions
The GPL and LGPL licenses require that if a modified version of software covered by those licenses is distributed, then the modified version, including source code must also be released under the same license.
Other licenses have fewer requirements, but may require that the original license notice accompany modified versions.
For questions, please contact licensing@firstworks.com.
Contributed Code
Patches and other contributions are welcome.
In order that the primary copyright holder may enforce the GPL and license exceptions most effectively, each author of code contributed to the GPL-licensed components of SQL Relay must provide the following copyright assignment:
The author or authors of this code assign any and all copyright interest in this code to David Muse, who is, at this time, the principal author and primary copyright holder of SQL Relay. We intend this dedication to be an overt act of assignment in perpetuity of all present and future rights to this code under copyright law.
If the contributed code was developed in the author's capacity as an employee, then the assignment must be made on company letterhead and signed by a company officer.
For questions or to submit copyright assignments, please contact licensing@firstworks.com.
Note that the information above is provided for reference only and shall not be considered authoritative. Please refer to the file COPYING at the root of the source or binary
distribution of each version of SQL Relay or the file LICENSE at the root of the binary distribution of each version of the SQL Relay Enterprise Modules for authoritative license details.