Drawing on the "Integration of Four Maps" from the "Jiaxing Experience", and starting from Beijing's own data context, this paper proposes a "Integration of Four Databases" workflow. This model is based on four operational tasks: New Fundamental Surveying and Mapping (NFSM), National Land Change Survey (NLCS), Urban Territorial Spatial Monitoring (UTSM), and Territorial Spatial Planning (TSP). It aims to resolve the issue of accumulating discrepancies in conflicting land use polygons by refining these polygons. This enables high-precision verification of NLCS data by NFSM data and facilitates the detection of dynamic changes. Differences are gradually "digested" year by year to achieve the goal of integration. Concurrently, it proposes using NFSM data to resolve building spatial location information, and UTSM to resolve operational building information. This achieves a dual expansion in both content and elements for NFSM and UTSM, progressively leading to reliable and accurate data on changes in building floor area and volume, thereby providing accurate data for leadership decision-making and urban planning in Beijing.