- "It's incredibly redundant."
- ―Dr. Radek Zelenka on the database's ability to back up data[src]
The Atlantis database also known as the Ancient database is the central computer database containing the knowledge the Ancients gained up to when they left Atlantis. The database can be accessed anywhere in the city, but the holo room is the best place to start for first-time users. The room is known to take a toll on power relative to the terminals and the power of a Naquadah generator, however, so the Atlantis expedition uses it sparingly. Ganos Lal devised a teaching program to instruct younger Lanteans using the information in the database. (SG1: "The Pegasus Project", SGA: "Rising", "The Siege, Part 2")
The exact size of the database relative to Earth data storage is unknown. Dr. McKay devised an advanced compression program to allow optimal data storage. However, given the limited amount of drives available at the time, Radek believed less than 10% of the portion they had deciphered at that point could be taken with them, had they evacuated. (SGA: "The Siege, Part 1")
Known information stored in the database includes:
- Historical archives including records of the Lantean-Wraith war
- Stargate addresses in both the Milky Way and Pegasus galaxies
- Information on these planets such as populations, solar data and Ancient notes
- An Ancient star map
- The nine-symbol Stargate address that leads to the Ancient ship Destiny, minus the point of origin
- ZPM research (which has yet to be fully understood by the Atlantis expedition)
- Shield schematics (which have yet to be fully understood by the Atlantis expedition)
- Ascension research (which has yet to be fully understood by the Atlantis expedition )
- Weapons schematics (which have yet to be fully understood by the Atlantis expedition)
- Cultural information on the natives of the Pegasus galaxy
- Biological notes and research
- Notes on space travel
- Information on the Wraith and the Iratus bug.
- A list of Lanteans who returned to Earth after the war with the Wraith .
- Archival visual records of each Lantean
- Details on the Mini-drone weapons
- Personal logs
- Schematics of Atlantis
