Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/1 Copyright © 2004 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 A Data Structures for Database Processing

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/3 Copyright © 2004 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

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/4 Copyright © 2004 Flat Files  A flat file is a file that has no repeating groups  They are usually processed in some predetermined order

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/5 Copyright © 2004 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

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/6 Copyright © 2004 Example: Sequential Lists

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/7 Copyright © 2004 Example: Linked Lists

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/8 Copyright © 2004 Example: Circular Linked Lists

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/9 Copyright © 2004 Example: Two-Way Linked Lists

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/10 Copyright © 2004 Example: Indexes

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/11 Copyright © 2004 Example: B-Trees

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/12 Copyright © 2004 Example: B-Trees

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/13 Copyright © 2004 Summary of Data Structures

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/14 Copyright © 2004 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

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/15 Copyright © 2004 Example: Tree Structure

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/16 Copyright © 2004 Example: Simple Network

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/17 Copyright © 2004 Example: Complex Network

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/18 Copyright © 2004 Representing Trees  Sequential lists, linked lists, and indexes can be used to represent trees

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/19 Copyright © 2004 Representing Trees with Sequential List

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/20 Copyright © 2004 Representing Trees with Linked List

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/21 Copyright © 2004 Representing Trees with Indexes

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/22 Copyright © 2004 Representing Simple Networks  Simple networks can be decomposed into trees and then represented

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/23 Copyright © 2004 Representing Simple Networks with Linked List

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/24 Copyright © 2004 Representing Simple Networks with Indexes

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/25 Copyright © 2004 Representing Complex Networks  Complex networks can be decomposed into simple networks containing an intersection record and then represented

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/26 Copyright © 2004 Representing Complex Networks with Linked List

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/27 Copyright © 2004 Relationship Representations Summary

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/28 Copyright © 2004 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

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/29 Copyright © 2004 Representing Secondary Keys With Linked List

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/30 Copyright © 2004 Representing Unique Secondary Keys with Indexes

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/31 Copyright © 2004 Representing Non-Unique Secondary Keys with Indexes

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/32 Copyright © 2004 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

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. KroenkeAppendix A/33 Copyright © 2004 Reminder DO NOT FORGET TO SIGN THE ATTENDANCE SHEET BEFORE YOU LEAVE TONIGHT

Fundamentals, Design, and Implementation, 9/e Appendix A Data Structures for Database Processing