I am considering developing an application that relies on MySQL as for database functionality. The application would include MySQL client API calls and be linked with MySQL libraries. It would be distributed with the MySQL database. According to the license terms in MySQL 3.23.30 Reference Manual (section 3.1): "A license is required if: You link a part of the of MySQL that has a GPL Copyright to a program that is not free software (embedded usage of the MySQL server). In this case your application would also become GPL through the clause in the GPL license that acts as a virus. By licensing MySQL from us under a commercial license you will avoid this problem. You have a commercial application that ONLY works with MySQL and ships the application with the MySQL server. This is because we view this as linking even if it is done over the network. You have a distribution of MySQL and you don't provide the source code for your copy of the MySQL server, as defined in the GPL license." The statement, "You have a commercial application that ONLY works with MySQL and ships the application with the MySQL server. This is because we view this as linking even if it is done over the network." is troubling because it appears to violate the intent if not the terms of the GPL/LGPL licensing. I read this statement as saying that if you develop a commercial application that relies only on MySQL for its database functionality, then you have to get a commercial license for your product or else your product becomes GPL itself. How can this be since MySQL is GPL and its client libraries that are linked into the application are LGPL? The commercial application should be able to freely incorporate the LGPL libraries and still be distributed for profit like other applications that incorporate LGPL libraries. The fact that an application that is a MySQL client works only with MySQL database should not have any effect on licensing. This is no different than a commercial Linux application that incorporates the Linux LGPL libraries and works only with the GPL Linux Operating System. In this case the commercial Linux application can be distributed for profit, it does not require a "special" license and it does not become GPL. How is an application, which incorporates the LGPL MySQL libraries and relies on the GPL MySQL to run, different from the previously described Linux application? MySQL's license uses the GPL "virus" clause to justify its licensing. Doesn't the reference to the virus clause under the GPL license basically have to do with repackaging a GPL component into proprietary software. In other words, if an application wraps GPL components then the application itself becomes GPL. However, an application that is a client to the MySQL database is not wrapping but acting as a user to the GPL MySQL software in the same way that a Linux application acts as a user of the GPL Linux operating system software. The only linkage in both cases is through APIs in the LGPL libraries. I can't see the distinction. Any thoughts? Jeff
