Did you actually click on the store link and look at what they are selling? You can use MySQL from home or commercial use free of charge.
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How do I purchase MySQL Products and Services?
MySQL offers MySQL Network, Training, Certification, and Consulting.
Purchase from our Online Shop
The easiest way to get MySQL Network, Training and Certification is to purchase directly from our online shop. You can order online by credit card and be on your way to higher reliability and security in minutes!