6.1 CHAPTER 6. MANAGING DATA RESOURCES

6.2 LEARNING OBJECTIVES COMPARE TRADITIONAL FILE ORGANIZATION & MANAGEMENT TECHNIQUESCOMPARE TRADITIONAL FILE ORGANIZATION & MANAGEMENT TECHNIQUES EXPLAIN PROBLEMS OF TRADITIONAL FILE ENVIRONMENTEXPLAIN PROBLEMS OF TRADITIONAL FILE ENVIRONMENT DESCRIBE HOW DATABASE MANAGEMENT SYSTEM ORGANIZES INFORMATIONDESCRIBE HOW DATABASE MANAGEMENT SYSTEM ORGANIZES INFORMATION*

6.3 LEARNING OBJECTIVES IDENTIFY TYPES OF DATABASE, PRINCIPLES OF DATABASE DESIGNIDENTIFY TYPES OF DATABASE, PRINCIPLES OF DATABASE DESIGN DISCUSS DATABASE TRENDSDISCUSS DATABASE TRENDS ANALYZE MANAGERIAL, ORGANIZATIONAL REQUIREMENTS FOR CREATING DATABASE ENVIRONMENTANALYZE MANAGERIAL, ORGANIZATIONAL REQUIREMENTS FOR CREATING DATABASE ENVIRONMENT*

6.4 MANAGEMENT CHALLENGES TRADITIONAL DATA FILE ENVIRONMENTTRADITIONAL DATA FILE ENVIRONMENT DATABASE ENVIRONMENTDATABASE ENVIRONMENT DESIGNING DATABASESDESIGNING DATABASES DATABASE TRENDSDATABASE TRENDS MANAGEMENT REQUIREMENTS FOR DATABASE SYSTEMSMANAGEMENT REQUIREMENTS FOR DATABASE SYSTEMS*

6.5 FILE ORGANIZATION BIT: Binary Digit (0,1; Y,N; On,Off)BIT: Binary Digit (0,1; Y,N; On,Off) BYTE: Combination of BITS which represent a CHARACTERBYTE: Combination of BITS which represent a CHARACTER FIELD: Collection of BYTES which represent a DATUM or FactFIELD: Collection of BYTES which represent a DATUM or Fact RECORD: Collection of FIELDS which reflect a TRANSACTIONRECORD: Collection of FIELDS which reflect a TRANSACTION*

6.6 FILE ORGANIZATION FILE: A Collection of Similar RECORDSFILE: A Collection of Similar RECORDS DATABASE: An Organization’s Electronic Library of FILESDATABASE: An Organization’s Electronic Library of FILES*

6.7 FILE ORGANIZATION ENTITY: Person, Place, Thing, Event about Which Data Must be KeptENTITY: Person, Place, Thing, Event about Which Data Must be Kept ATTRIBUTE: Description of a Particular ENTITYATTRIBUTE: Description of a Particular ENTITY KEY FIELD: Field Used to Retrieve, Update, Sort RECORDKEY FIELD: Field Used to Retrieve, Update, Sort RECORD*

6.8 KEY FIELD Field in Each Record Uniquely Identifies THIS Record For RETRIEVAL UPDATING UPDATINGSORTING*

6.9 SEQUENTIAL VS. DIRECT FILE ORGANIZATION SEQUENTIAL: Tape Oriented; One File Follows Another; Follows Physical SequenceSEQUENTIAL: Tape Oriented; One File Follows Another; Follows Physical Sequence DIRECT: Disk Oriented; Can be Accessed Without Regard to Physical SequenceDIRECT: Disk Oriented; Can be Accessed Without Regard to Physical Sequence*

6.10 FILING METHODS INDEXED SEQUENTIAL ACCESS METHOD (ISAM) :INDEXED SEQUENTIAL ACCESS METHOD (ISAM) : –EACH RECORD IDENTIFIED BY KEY –GROUPED IN BLOCKS AND CYLINDERS –KEYS IN INDEX VIRTUAL STORAGE ACCESS METHOD (VSAM) :VIRTUAL STORAGE ACCESS METHOD (VSAM) : –MEMORY DIVIDED INTO AREAS & INTERVALS –DYNAMIC FILE SPACE VSAM WIDELY USED FOR RELATIONAL DATABASES VSAM WIDELY USED FOR RELATIONAL DATABASES DIRECT FILE ACCESS METHODDIRECT FILE ACCESS METHOD*

6.11 DIRECT FILE ACCESS METHOD EACH RECORD HAS KEY FIELDEACH RECORD HAS KEY FIELD KEY FIELD FED INTO TRANSFORM ALGORITHMKEY FIELD FED INTO TRANSFORM ALGORITHM ALGORITHM GENERATES PHYSICAL STORAGE LOCATION OF RECORD (RECORD ADDRESS)ALGORITHM GENERATES PHYSICAL STORAGE LOCATION OF RECORD (RECORD ADDRESS)*

6.12 DATA REDUNDANCYDATA REDUNDANCY PROGRAM / DATA DEPENDENCYPROGRAM / DATA DEPENDENCY LACK OF FLEXIBILITYLACK OF FLEXIBILITY POOR SECURITYPOOR SECURITY LACK OF DATA SHARING & AVAILABILITYLACK OF DATA SHARING & AVAILABILITY* TRADITIONAL FILE ENVIRONMENT (FLAT FILE)

6.13 DATABASE ORGANIZATION’S ELECTRONIC LIBRARY STORES & MANAGES DATA IN A CONVENIENT FORM *

6.14 DATABASE MANAGEMENT SYSTEM (DBMS) SOFTWARE TO CREATE & MAINTAIN DATA ENABLES BUSINESS APPLICATIONS TO EXTRACT DATA ENABLES BUSINESS APPLICATIONS TO EXTRACT DATA INDEPENDENT OF SPECIFIC COMPUTER PROGRAMS INDEPENDENT OF SPECIFIC COMPUTER PROGRAMS* DBMS

6.15 COMPONENTS OF DBMS: DATA DEFINITION LANGUAGE:DATA DEFINITION LANGUAGE: –Defines data elements in database DATA MANIPULATION LANGUAGE:DATA MANIPULATION LANGUAGE: –Manipulates data for applications DATA DICTIONARY:DATA DICTIONARY: –Formal definitions of all variables in database; controls variety of database contents * DBMS

6.16 STRUCTURED QUERY LANGUAGE (SQL) EMERGING STANDARD DATA MANIPULATION LANGUAGE FOR RELATIONAL DATABASES * DBMS

6.17 TWO VIEWS OF DATA BIT BYTE FIELD RECORD FILE DATABASE PHYSICAL VIEW: Where is data physically?PHYSICAL VIEW: Where is data physically? –DRIVE, DISK, SURFACE, TRACK, SECTOR (BLOCK), RECORD –TAPE, BLOCK, RECORD NUMBER (KEY) LOGICAL VIEW: What data is needed by application?LOGICAL VIEW: What data is needed by application? –SUCCESSION OF FACTS NEEDED BY APPLICATION –NAME, TYPE, LENGTH OF FIELD * DBMS

6.18 RELATIONAL DATA MODEL DATA IN TABLE FORMATDATA IN TABLE FORMAT RELATION: TABLERELATION: TABLE TUPLE: ROW (RECORD) IN TABLETUPLE: ROW (RECORD) IN TABLE FIELD: COLUMN (ATTRIBUTE) IN TABLEFIELD: COLUMN (ATTRIBUTE) IN TABLE*

6.19 TYPES OR RELATIONS ONE-TO-ONE: STUDENT ID ONE-TO-MANY: CLASS STUDENT A STUDENT B STUDENT C MANY-TO-MANY: STUDENT A STUDENT B STUDENT C CLASS 1 CLASS 2

6.20 ROOT FIRST CHILD 2nd CHILD RatingsSalary Compensation Job Assignments PensionInsuranceHealth Benefits Employer HIERARCHICAL DATA MODEL

6.21 NETWORK DATA MODEL VARIATION OF HIERARCHICAL MODELVARIATION OF HIERARCHICAL MODEL USEFUL FOR MANY-TO-MANY RELATIONSHIPSUSEFUL FOR MANY-TO-MANY RELATIONSHIPS* NETWORK A NETWORK B NETWORK C NETWORK 1 NETWORK 2

6.22 OTHER SYSTEMS LEGACY SYSTEM: older systemLEGACY SYSTEM: older system OBJECT-ORIENTED DBMS: stores data & procedures as objectsOBJECT-ORIENTED DBMS: stores data & procedures as objects OBJECT-RELATIONAL DBMS: hybridOBJECT-RELATIONAL DBMS: hybrid*

6.23 CREATING A DATABASE CREATING A DATABASE CONCEPTUAL DESIGNCONCEPTUAL DESIGN PHYSICAL DESIGNPHYSICAL DESIGN*

6.24 CREATING A DATABASE CONCEPTUAL DESIGN: CREATING A DATABASE CONCEPTUAL DESIGN: ABSTRACT MODEL, BUSINESS PERSPECTIVEABSTRACT MODEL, BUSINESS PERSPECTIVE HOW WILL DATA BE GROUPED?HOW WILL DATA BE GROUPED? RELATIONSHIPS AMONG ELEMENTSRELATIONSHIPS AMONG ELEMENTS ESTABLISH END-USER NEEDSESTABLISH END-USER NEEDS*

6.25 CREATING A DATABASE PHYSICAL DESIGN: CREATING A DATABASE PHYSICAL DESIGN: DETAILED MODEL BY DATABASE SPECIALISTSDETAILED MODEL BY DATABASE SPECIALISTS ENTITY-RELATIONSHIP DIAGRAMENTITY-RELATIONSHIP DIAGRAM NORMALIZATIONNORMALIZATION HARDWARE / SOFTWARE SPECIFICHARDWARE / SOFTWARE SPECIFIC*

6.26 ENTITY- RELATIONSHIP DIAGRAM 1 1 M 1 ORDER CAN HAVE PART SUPPLIER CAN HAVE ORDER: #, DATE, PART #, QUANTITY PART: #, DESCRIPTION, UNIT PRICE, SUPPLIER # SUPPLIER: #, NAME, ADDRESS

6.27 NORMALIZATION PROCESS OF CREATING SMALL DATA STRUCTURES FROM COMPLEX GROUPS OF DATA EXAMPLES: ACCOUNTS RECEIVABLEACCOUNTS RECEIVABLE PERSONNEL RECORDSPERSONNEL RECORDS PAYROLLPAYROLL*

6.28 DISTRIBUTED DATABASES PARTITIONED: remote CPUs (connected to host) have files unique to that site, e.g., records on local customersPARTITIONED: remote CPUs (connected to host) have files unique to that site, e.g., records on local customers DUPLICATE: each remote CPU has copies of common files, e.g., layouts for standard reports and formsDUPLICATE: each remote CPU has copies of common files, e.g., layouts for standard reports and forms*

6.29 DATABASE TRENDS MULTIDIMENSIONAL DATA ANALYSIS: 3D (or higher) groupings to store complex dataMULTIDIMENSIONAL DATA ANALYSIS: 3D (or higher) groupings to store complex data HYPERMEDIA: Nodes contain text, graphics, sound, video, programs. organizes data as nodes.HYPERMEDIA: Nodes contain text, graphics, sound, video, programs. organizes data as nodes.*

6.30 DATABASE TRENDS DATA WAREHOUSE: Organization’s electronic library stores consolidated current & historic data for management reporting & analysisDATA WAREHOUSE: Organization’s electronic library stores consolidated current & historic data for management reporting & analysis DATA MART: Small data warehouse for special function, e.G., Focused marketing based on customer infoDATA MART: Small data warehouse for special function, e.G., Focused marketing based on customer info*

6.31 COMPONENTS OF DATA WAREHOUSE

6.32 DATABASE TRENDS ON-LINE ANALYTICAL PROCESSING (OLAP): ability to manipulate, analyze large volumes of data from multiple perspectivesON-LINE ANALYTICAL PROCESSING (OLAP): ability to manipulate, analyze large volumes of data from multiple perspectives LINKING DATABASES TO THE WEBLINKING DATABASES TO THE WEB*

6.33 ELEMENTS OF DATABASE ENVIRONMENT DATABASE MANAGEMENT SYSTEM DATA ADMINISTRATION DATABASE TECHNO LOGY & MANAGEMENT USERS DATA PLANNING & MODELING METHODOLOGY

6.34 DATABASE ADMINISTRATION DEFINES & ORGANIZES DATABASE STRUCTURE AND CONTENTDEFINES & ORGANIZES DATABASE STRUCTURE AND CONTENT DEVELOPS SECURITY PROCEDURESDEVELOPS SECURITY PROCEDURES DEVELOPS DATABASE DOCUMENTATIONDEVELOPS DATABASE DOCUMENTATION MAINTAINS DBMSMAINTAINS DBMS*

6.35 Connect to the INTERNET Laudon/Laudon Web site: Additional Internet Resources related to this chapter: news:comp.databases news:comp.databases.theory © 2001 Laudon & Laudon, Essentials of Management Information Systems 4/e

6.36 CHAPTER 6. MANAGING DATA RESOURCES