Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/1 Copyright © 2004 Please……. No Food Or Drink in the class

Appendix A/1 Copyright © 2004

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. Kroenke

Please…….No Food Or Drink in the class room

Cell phones off

Pagers on vibrate

Phasers on stun

Fundamentals, Design, and Implementation, 9/e

Appendix AData Structures for Database Processing



Objectives

Define the term data structures Define and illustrate the terms flat file,

sequential list, linked list ,and index Define and illustrate the B-Tree multilevel

indexes Demonstrate how binary relationships are

represented using trees, simple networks, and complex networks

Define and illustrate primary and secondary keys

Define and illustrate unique and non-unique secondary keys



Flat Files

A flat file is a file that has no repeating groups They are usually processed in some

predetermined order



Processing Flat Files

Flat files can be ordered using the following data structures– Sequential lists: physically placing the records in the

sequence in which they will be processed– Linked lists: attaching to each data record a pointer to

another logically related record– Indexes or inverted list: building a table, separate from

the data records that contains pointers to related records• B-trees are special applications of indexes

Data structures can be used to represent record relationships as well as secondary keys



Example: Sequential Lists



Example: Linked Lists



Example: Circular Linked Lists



Example: Two-Way Linked Lists



Example: Indexes



Example: B-Trees



Example: B-Trees



Summary of Data Structures



Record Relationships

Records can be related in three ways– A tree relationship has 1:N relationships with

each child record has only one parent– A simple network is a collection of records and

the 1:N relationships among them– A complex network is a collection of records

and N:M relationships



Example: Tree Structure



Example: Simple Network



Example: Complex Network



Representing Trees

Sequential lists, linked lists, and indexes can be used to represent trees



Representing Trees with Sequential List



Representing Trees with Linked List



Representing Trees with Indexes



Representing Simple Networks

Simple networks can be decomposed into trees and then represented



Representing Simple Networks with Linked List



Representing Simple Networks with Indexes



Representing Complex Networks Complex networks

can be decomposed into simple networks containing an intersection record and then represented



Representing Complex Networks with Linked List



Relationship Representations Summary



Secondary Key Representations

Secondary keys are used to access the data on some field besides the primary key

Secondary keys can be unique or non-unique– Non-unique secondary keys can be represented with

both linked lists and indexes– Unique secondary keys can be represented only with

indexes



Representing Secondary Keys With Linked List



Representing Unique Secondary Keys with Indexes



Representing Non-Unique Secondary Keys with Indexes



Summary

A flat file is a file that contains no repeating groups

Flat files can be ordered both physically and logically

B-trees are special applications of indexes There are three basic record structures

– Trees– Simple Networks, and– Complex Networks



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TONIGHT

Fundamentals, Design, and Implementation, 9/e

Appendix AData Structures for Database Processing

Documents

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/1 Copyright © 2004 Please……. No Food Or Drink in the class