依照MySQL AB所提供的資料，需要購買商業版的情況如下：
If you use MySQL software but don't want to adhere to the GPL, you can purchase a commercial license from MySQL AB.

If your application isn't licensed under GPL or a compatible Open Source Initiative (OSI) license approved by MySQL AB and you intend to distribute MySQL software (either internally or externally), you must first obtain a commercial license for the MySQL software in question. More specifically:

If you include the MySQL server in your non-open source application, you need a commercial license for the MySQL server.

If you include one or more of the MySQL drivers in your non-open source application so that your application can run with MySQL, you need a commercial license for the drivers in question. The MySQL drivers currently include the libmysqlclient C client library, MySQL Connector/ODBC, and MySQL Connector/J.

If you use MySQL software within your organization and you don't want to risk having it fall under the GPL license, you should purchase a commercial license.

Many users opt for the commercial license simply because, under it, MySQL AB takes responsibility for its products. Under the GPL license, there are no warranties or representations from the developer, which is MySQL AB in this case.

需要的人看一下吧

MySQL ...啊~心中的痛