Chapter A:Network Model Basic Concepts Data-Structure Diagrams The DBTG CODASYL Model DBTG Data-Retrieval Facility DBTG Update Facility DBTG Set-Processing Facility Mapping of Networks to Files Database System Concepts,5th Ed. A.1 @Silberschatz,Korth and SudarshanDatabase System Concepts, 5 A.1 ©Silberschatz, Korth and Sudarshan th Ed. Chapter A: Network Model Basic Concepts Data-Structure Diagrams The DBTG CODASYL Model DBTG Data-Retrieval Facility DBTG Update Facility DBTG Set-Processing Facility Mapping of Networks to Files