Advanced Database Gateway The FAO Land Cover Classification System software is due to be released in its third version, and with it come four supporting volumes. The third volume is a tutorial for the use of the Advanced Database Gateway which allows users to better interact with the LCCS and adapt it to their needs. The FAO LCCS is applicable to commercial use, national security, environmental protection, natural resource management, climate change mitigation and tracking of greenhouse gas emissions; and creates land classifications that are internationally transparent and comparable.