Entity-Relationship Model - ISA Inheritance | Database Tutorial 3f скачать в хорошем качестве

Entity-Relationship Model - ISA Inheritance | Database Tutorial 3f

In this lecture of the databases course we learn about ISA inheritance in the entity-relationship model (ER model). This is also known as ISA specialization (or generalization). We will see that the ISA can be annotated with constraints disjoint (default is overlapping) and total specialization (every higher-level entity must belong to at least one of the lower-level entity sets). This is the databases online course given at the Vrije Universiteit Amsterdam by Jörg Endrullis. The course objective is to obtain a good understanding of relational database systems from the user perspective. This includes the ability to develop conceptual database models, as well as key concepts and skills in relational database theory and practice. Among others, we treat in this course the following subjects: (a) entity–relationship diagrams for the design of database schemata, (b) the relational database model and integrity constraints, (c) SQL (structured query language) for retrieving information from relational databases, (d) database normalisation and functiona dependencies (reasoning about good database design), (e) transactions and concurrency control. The slides are based on work by Peter Boncz and Torsten Grust.