Object-Based Databases
Complex Data Types
atomic data item of type string
Structured Types and Inheritance in SQL
Structured Types
Type Inheritance
composite attributes of E-R designs to be represented
directly
types to create composite attributes in a relation
methods
store extra information in the database
extra field at the end of the type definition
most-specific type
Table Inheritance
the E-R notion of specialization/generalization
subtables
subtypes
of the type of the parent table
a subtable and parent
table correspond
SQL has an additional constraint that all the tuples corresponding to each other must be derived from one tuple (inserted into one table)
Each tuple of the supertable can correspond to at most one tupl
in each of its immediate subtables.
Array and Multiset Types in SQL
Creating and Accessing Collection Values
Querying Collection-Valued Attributes
Nesting and Unnesting
unnesting
nested relation into a form with fewer (or no) relationvalued attributes
nesting
reverse process of transforming a 1NF relation into a nested
Object-Identity and Reference Types in SQL
restriction of
the scope of a reference
self-referential attribute
Implementing O-R Features
Each table stores the primary key
Each table stores all inherited and locally defined attributes
Persistent Programming Languages
Persistence of Objects
Persistence by marking
Persistence by reachability
Persistence by creation
Persistence by class
Object Identity and Pointers
Intraprogram
Interprogram
Intraprocedure.
Persistent
Storage and Access of Persistent Objects
not scale to millions of objects
Persistent C++ Systems
Relationships
Iterator interface
Class extents
Transactions
Creation of persistent objects
Persistent pointers
Updates
Query language
Persistent Java Systems
Byte code enhancement
Database mapping
Persistence by reachability
Class extents
Single reference type
Object-Relational Mapping
Object-Oriented versus Object-Relational
Persistent programming language–based OODBs
Object-relational systems
Relational systems
Object-relational mapping systems
Silberschatz, A., Korth, H., & Sudarshan, S. (2019). Database System Concepts (7a ed.). McGraw-Hill.
Alvaro Moreira Villalobos