Digital SNOWTAM Trial AIXM Database Design Pulsar Consulting

Digital SNOWTAM Trial: AIXM Database Design Pulsar Consulting sa Avenue Pasteur, 17 1300 Wavre Belgium Tel : +32 10 43 51 00 Fax : +32 10 43 51 01 Web: www. pulsar. be

Agenda • General Guidelines • Temporality Model Implementation • Common Properties and Geoms • Notes Implementation • ICAO SNOWTAMs Implementation (not included in AIXM) • Null Properties Implementation (x. NOTAM-Trial)

General Guidelines § Implemented only a subset of AIXM 5. x § Manual design (no generation) § As close as possible to the AIXM Conceptual Model § One table per class for <<feature>> and <<object>> § Inheritance generally not applied at the database level § Inherited fields repeated in each table - avoid too many joins § Notes and many to many relationships § Enumerations database constraint (!! AIXM 5. 1 !!)

Temporality Model Implementation Timeslice types: § BASELINE § PERMDELTA § TEMPDELTA § STATE (~ long SNAPSHOT) (interpretation) Fields about temporality are repeated in all timeslice tables to avoid having to many joins (valid. Time, interpretation, sequence. Number, etc…)

Common Properties and Geoms * Added technical fields in all tables § Tracing information § Pre-calculated information and aggregated geoms § Runway thirds geoms

Notes Implementation § One Note table linked to all timeslices tables (many to many) § No constraint on property_name (but managed by applications)

ICAO SNOWTAMs Implementation (not included in AIXM) § The timeslices impacted by a SNOWTAM are linked to the associated SNOWTAM. Furthermore, the ICAO SNOWTAM is linked to its associated Airport. Heliport Feature:

NULL Properties Implementation § Timeslices may explicitly set a property to ‘NULL’: means this property has no value anymore (the property is changed to ‘NULL’). § In Digital NOTAM Trial: new “is null” boolean property for each nullable simple or complex property = concatenation of the property name and the suffix “_N” (was generated from the db schema) § Not needed in Digital SNOWTAM. Contaminations last no more than 24 hours and a “green” SNOWTAM is emitted for ‘all clear’ situation

QUESTIONS