[snuxoll]

Requiring GPL’d software to function means your product is a derivative work, full stop as far as the spirit and letter of the license is concerned. Using it over a network instead of linking against it doesn’t change this, if you depend on MySQL or any of the forks and distribute your software it must be made available under a GPL-compatible license. The requirements of the AGPL become clear in this regard as well; network use is distribution with the AGPL - incorporating AGPL’d software into your application means you must consider your entire application as licensed under the AGPL or compatible license.

MongoDB muddied the waters here by deciding to interpret the AGPL differently, but I wouldn’t risk your business on it.