You are right r937, I am looking for something like MS SQL Server does as UUID. Here is a mail reply that I've got from Arthur Fuller due to the fact:
Unfortunately, there is no such datatype in MySQL. I have been researching the theory and practice of GUIDs but have not developed a routine yet that will enable their manufacture as easily as NewID() does in MS-SQL. It's on my to-do list, however.
By the way, I managed to accomplished it through PHP function $MyGUID = md5(uniqid(rand(0, 1000),1)); that returns stuff like '0cd7b66f936684b913562149e6e49034', but I am not certain if it guarantees to be unique like MS SQL Server.