Цитат:
What is MySQL's software licensing model?
MySQL uses a "dual licensing" business model. Under this model, users may choose to use MySQL products under the free software/open source GNU General Public License (commonly known as the "GPL") or under a commercial license.
With the GPL license, MySQL is available free of charge, as long as the use of MySQL adheres to the terms of GPL license. Users may download the software for free and modify, integrate and distribute it. [b]However, GPL users must abide by the rules of the GPL, which stipulate that if a MySQL-based application is redistributed, the complete source code for this application must also be open and available for redistribution.
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