Archer using the Xindi database aboard the Enterprise
A Xindi database was once stolen by Enterprise from an Osaarian merchant ship. Forcibly downloaded by comm link as the Enterprise flew less than a kilometer away from the Osaarians, the database was retrieved only with the use of access codes provided by an Osaarian that Captain Archer was holding in the brig.
It contained comprehensive data about the Xindi, about whom neither the United Earth Starfleet nor the Vulcan High Command knew much. At the time, its recovery was therefore a significant intelligence victory in the war with the Xindi.
Archer used this database to find information about the Xindi superweapon. (ENT: "Anomaly") It was through this database that Archer and T'Pol first became aware of the Xindi-Arboreals. However, other information proved more elusive. He once spent hours just trying to understand the way Xindi organized their star charts. (ENT: "Extinction")