I'm trying out the free trial of azure with an a wordpress installation and therefor created a cleardb mysql database. The database was created with the free version and has a very poor performance. However I don't know if I can use my free testrail too scale up the db because the cleardb mysqly database because there I would have to reenter my credit card details...
So are cleardb upgrades also included in the free azure trail?
Mercury plan(free) for ClearDB MySQL is just for testing/development, it has just 4 maximum connections and this is not designed for production environments. Please try to get MySQL on VM for WordPress if you prefer to pay less.
Check this reference: https://azure.microsoft.com/en-us/blog/word-press-solution-template-using-azure-virtual-machines/