I pulled this from the secretary of state website. Maybe it'll help.
What is the difference between a Fictitious Name and a Doing Business As (DBA)?
A Fictitious Name and a DBA are one and the same. They can also be known as "trade names." At times, a DBA is used when a company decides to do business under a name other than that in which they are registered. Pursuant to O.C.G.A. 10-1-490 trade names are registered with the Clerk of Superior Court of the county where the business is principally located.