TRENDS IN DATABASE TECHNOLOGY - Database Design and Development: An Essential Guide for IT Professionals - page 672

Region query Relates to whole or partial regions. Query may request for objects
partially or fully inside a region. Example: Show me the rivers flowing through the
state of Louisiana.
Proximity query Requests for objects near a given place. Example: Show me the
Italian restaurant nearest to the intersection of Georges Road and Fifth Street.
Intersection and union query Requests of information obtained through inter-
section or union. Example: Show me the areas in the metropolitan region with low
crime rate and low population density.
CHAPTER SUMMARY
• Data abstraction, inheritance, and object identity form the basis for object ori-
entation.
• In object technology, an object is a single, uniquely identifiable entity. Objects
having the same attributes and performing the same operations constitute a
class. Methods indicate the behavior of an object. Messages are the means for
communication between objects.
• Object-oriented database systems address some of the limitations of relational
database systems. Object-oriented databases combine database capabilities
with object orientation.
• Object-relational databases are emerging from a combination of object orien-
tation and relational database technology.
• A certain set of distinct features makes ORDBMS better than RBDMS and
OODBMS: base data type extension, support for complex objects, support for
large objects, ability to define new data types and functions, and a flexible rule
system.
• Special types of database systems provide information for decision support
systems such as data warehousing, OLAP, and data mining.
• A data warehouse is a new type of system environment designed for strategic
information. OLAP enables highly multidimensional analysis and complex cal-
culations. Data mining is a knowledge discovery process uncovering patterns
and relationships from data.
• Leading trends in database technology: parallel databases, active databases,
intelligent databases, deductive databases, multimedia databases, mobile data-
bases, and geographic databases.
REVIEW QUESTIONS
1. Briefly describe the concept of data abstraction in object technology.
2. Describe objects and classes with examples.
3. List the advantages and disadvantages of OODBMS.
4. Define an ORDBMS. What are its major features?