Fig. 1
From: Urban morphogenesis analysis based on geohistorical road data
A simplified physical data model of the COVADEO geohistorical database. The present-day road segments are also stored in the geohistorical database. They are obtained from the 2019 French national database (BD Topo 2019)5 that contains road network vector information. The diagram is designed based on a UML model (Unified Modeling Language). Each cell represents a table in the database, with the name as header. Primary keys are listed in red, some main attributes are listed in black, and the main foreigner keys are listed in green for each table. The relationship indications between tables are as follows: 1—1 is the “one-to-one” relationship, 1–0.0.1 is “one-to-none or to one”, 1–1..n is “one-to one or to many” and 1–0..n is “one-to-none or to many”