DBSN – DATABASE DI SINTESI NAZIONALE (NATIONAL SYNTHESIS DATABASE)
INTRODUCTION
The DBSN ( Database di Sintesi Nazionale - National Synthesis Database) is a geographic database storing the most significant spatial information for carrying out thematic analysis and representations at national level. In order to realise the DBSN, aiming to process increasingly complete and up-to-date data, regional geotopographic data were mainly used as the primary source of information.
At the early stage of the project the latest updated data were collected and their structure was transformed to make them homogeneous at the national level, while maintaining the original level of detail. Afterwards, data were integrated with data from national public bodies, e.g., cadastral maps from the Internal Revenue Agency, data from Istat (Italian National Institute of Statistics), data from other ministries, while also considering other information available on the web such as Open Street Map (OSM) data. Where derived information was lacking, data were acquired directly from AGEA orthoimages. Especially in reworking the content, the road system was updated at least for major roads; administrative boundaries were derived from cadastral boundaries and a process to match municipal areas with each other and with the state boundaries was carried out; built-up area were classified according to main use categories. Place-names has been updated and standardized, enabling the publication of a specific service relating to geographical names (on the "HIGH-VALUE DATA" page).
The DBSN is continuously updated by acquiring and integrating new data.
From the content of the DBSN, in vector format, maps at scale 1:25,000 are derived through automatic procedures of cartographic generalization and application of the established symbology.
DBSN COVERAGE (LAST UPDATED AUGUST 2025)
All the provinces of Italy covering the area near the national border have been released (verified by the Geodetic Department, updated in June 2025).
New version (August 2025)
Compared to the previous one (2023) the new version includes important udates:
- completion of national coverage through the publication of data (Italian border);
- udate of the built-up area at national level;
- partial update of the most important areas of relevance;
- partial update of the road network for the main functional classification.
SPECIFICATIONS
The database structure is based on technical specifications according to those established by national legislation (Decree November 10th, 2011). The term "synthesis" refers to the selection of information and the simplification of the database structure: the content specifications of the DBSN are a sub-set of the "Catalogue of Spatial Data - Content Specifications for Geotopographic Databases," which resulted in the reduction from 159 to 91 classes divided into 10 layers (74 of which are releasable while the remaining ones have not been verified). The META_IST attribute has been introduced in the specifications for all classes with a list of predefined domains representing operational metadata indicating the source for each added object. The specifications are currently being revised according to the INSPIRE guidelines.
USER LICENSE
The DBSN Database (Database di Sintesi Nazionale) of the IGM is made available and licensed under the Open Data Commons Open Database License (ODbL)
ver. 1.0 https://opendatacommons.org/licenses/odbl/1-0/ .
METADATA
Metadata sheet
REGULATION
"Catalogue of Spatial Data - Content Specifications for Geotopographic Databases", annex to the Ministerial Decree of November 10th 2011 "Technical rules for defining the content specifications for geotopographic databases" (Official Journal no. 48 of 27/02/2012 - Ordinary Supplement no. 37).
Legislative Decree no. 36 of January 24th 2006, as amended, on open data and the re-use of public sector information.
DATA DOWNLOADING
Any request for information or feedback can be sent to: dbsn@igmi.org
