Just a word of warning, if your application is dependant on MySQL, you will need to purchase a MySQL distribution licence if you want to be able to legally sell your product. Otherwise the GPL license will prevail and legally you will have to distribute your source code under the GPL license to anyone that you normally have distributed your product to.
If you are an open-source shop, this isn't a problem. If you are a closed-source shop, you have three options: 1. Hope MySQL never finds out, 2. Purchase a distribution license with MySQL, 3. Port your application to Postgresql and never worry about database licensing again.
(I probably misspelled license, but at least I'm consistant on it.
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