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Database Design: Logical Models: Normalization and The Relational Model University of California, Berkeley School of Information IS 257: Database Management IS 257 – Fall 2012 2011.09.06 - SLIDE 1 Announcements • Assignment 1 due date extended to next Thursday - Sept. 13 • Assignment 2 (Personal database conceptual model) – due Sept. 20 IS 257 – Fall 2012 2011.09.06 - SLIDE 2 Lecture Outline • More on phpMyAdmin & MySQL • Review – Conceptual Model and UML • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 3 Lecture Outline • More on phpMyAdmin & MySQL • Review – Conceptual Model and UML • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 4 Rediscovered Full Queries • In phpMyAdmin there IS a way to do most of the SQL creation for queries by list selection and menu filling • The trick is to select the entire database (your login name) then a “Query” tab will appear • Demo… • Command Line – Login via SSH to ischool.berkeley.edu IS 257 – Fall 2012 2011.09.06 - SLIDE 5 Lecture Outline • More on phpMyAdmin • Review – Conceptual Model and UML • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 6 Class Diagrams • A class diagram is a diagram that shows a set of classes, interfaces, and/or collaborations and the relationships among these elements. IS 257 – Fall 2012 2011.09.06 - SLIDE 7 UML Class Diagram DIVEORDS Order No Customer No Sale Date Shipvia PaymentMethod CCNumber No of People Depart Date Return Date Destination Vacation Cost CalcTotalInvoice() CalcEquipment() IS 257 – Fall 2012 Class Name List of Attributes List of operations 2011.09.06 - SLIDE 8 Object Diagrams 307:DIVORDS Order No = 307 Customer No = 1480 Sale Date = 9/1/99 Ship Via = UPS PaymentMethod = Visa CCNumber = 12345 678 90 CCExpDate = 1/1/01 No of People = 2 Depart Date = 11/8/00 Return Date = 11/15/00 Destination = Fiji Vacation Cost = 10000 IS 257 – Fall 2012 2011.09.06 - SLIDE 9 Associations • An association is a relationship that describes a set of links between or among objects. • An association can have a name that describes the nature of this relationship. You can put a triangle next to this name to indicate the direction in which the name should be read. IS 257 – Fall 2012 2011.09.06 - SLIDE 10 Associations: Unary relationships * 0..1 Person 0..1 Is-married-to manages Employee 0..1 manager IS 257 – Fall 2012 2011.09.06 - SLIDE 11 Associations: Binary Relationship Employee 0..1 Is-assigned Parking Place 0..1 One-to-one Product Line 1 contains * Product One-to-many Student * Registers-for * Course Many-to-many IS 257 – Fall 2012 2011.09.06 - SLIDE 12 Associations: Ternary Relationships Part * Vendor IS 257 – Fall 2012 * Supplies * Warehouse 2011.09.06 - SLIDE 13 Association Classes Registers-for Student * Course * Computer Account Registration _________________ ________________ acctID Term issues Password * 0..1 Grade ServerSpace ________________ CheckEligibility() IS 257 – Fall 2012 2011.09.06 - SLIDE 14 Derived Attributes, Associations, and Roles Course Student Course Offering _________ ____________ ____________ Scheduled-for name Registers-for crseCode term ssn * crseTitle * * 1 section dateOfBirth creditHrs time Derived /age location attribute * * /participant Derived role {age = currentDate – dateOfBirth} /Takes Derived association IS 257 – Fall 2012 2011.09.06 - SLIDE 15 Generalization employee type Employee ____________ empName empNumber address dateHired ____________ printLabel() employee type Hourly Employee _______________ HourlyRate _______________ computeWages() IS 257 – Fall 2012 Salaried Employee _______________ AnnualSalary stockoption _______________ Contributepension() employee type Consultant _______________ contractNumber billingRate _______________ computeFees() 2011.09.06 - SLIDE 16 Lecture Outline • Review – Conceptual Model and UML • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 17 Database Design Process Application 1 External Model Application 2 Application 3 Application 4 External Model External Model External Model Application 1 Conceptual requirements Application 2 Conceptual requirements Application 3 Conceptual requirements Conceptual Model Logical Model Internal Model Application 4 Conceptual requirements IS 257 – Fall 2012 2011.09.06 - SLIDE 18 Logical Model: Mapping to a Relational Model • Each entity in the ER Diagram becomes a relation. • A properly normalized ER diagram will indicate where intersection relations for many-to-many mappings are needed. • Relationships are indicated by common columns (or domains) in tables that are related. • We will examine the tables for the Diveshop derived from the ER diagram IS 257 – Fall 2012 2011.09.06 - SLIDE 19 DiveShop ER Diagram Customer No DiveCust 1 Destination Name Destination no Customer No ShipVia n Dest n 1 DiveOrds n 1 ShipVia ShipVia 1 Destination no Site No 1 n Site No BioSite Species No 1 Destination n Sites Order No n 1 1/n ShipWrck Order No DiveItem n Item No n Site No 1 Species No BioLife IS 257 – Fall 2012 1 DiveStok Item No 2011.09.06 - SLIDE 20 Customer = DIVECUST Customer No Name Street City State/Prov Zip/Postal Code Country 1480 Louis Jazdzewski 2501 O'Connor New Orleans LA 60332 U.S.A. 1481 Barbara Wright 6344 W. Freeway San Francisco CA 95031 U.S.A. 1909 Stephen Bredenburg 559 N.E. 167 Indianapolis Place IN 46241 U.S.A. 1913 Phillip Davoust 123 First Street Berkeley CA 94704 U.S.A. 1969 David Burgett 320 Montgomery SeattleStreet WA 98105 U.S.A. 2001 Mary Rioux1701 Gateway Pueblo Blvd. #385 CO 81002 U.S.A. 2306 Kim Lopez 14134 Nottingham HonoluluLane HI 96826 U.S.A. 2589 Hiram Marley 7233 Mill Run SanDrive Francisco CA 94123 U.S.A. 3154 Tanya Kulesa 505 S. Flower, NewMail YorkStop NY 48943 10032 U.S.A. 3333 Charles Sekaron 110 East Park Miller Avenue,SD Box 8 57362 U.S.A. 3684 Lowell Lutz915 E. Fesler Dallas TX 75043 U.S.A. 4158 Keith Lucas56 South Euclid Chicago IL 60542 U.S.A. 4175 Karen Ng 2134 ElmhillKlamath Pike Falls OR 97603 U.S.A. 5510 Ken Soule 58 Sansome Aurora Street CO 89022 U.S.A. IS 257 – Fall 2012 Phone First Contact (902) 555-88881/29/95 (415) 555-43212/2/93 (317) 555-36441/5/93 (415) 555-91843/9/98 (206) 555-75803/12/99 (719) 555-20103/15/97 (808) 555-50501/29/99 (415) 555-64302/18/99 (212) 555-67501/30/99 (613) 555-43333/16/98 (214) 555-27222/15/99 (312) 555-43103/17/98 (503) 555-47003/20/99 (303) 555-66952/5/99 2011.09.06 - SLIDE 21 Dive Order = DIVEORDS Order No Customer NoSale Date Ship Via PaymentMethod CcNumber CcExpDate No Of PeopleDepart Date Return DateDestination VacationCost 307 310 1480 1481 9/1/99 UPS 9/1/99 FedEx Visa Check 313 314 317 320 321 325 1909 1913 1969 2001 2306 2589 9/1/99 9/1/99 9/1/99 9/1/99 9/1/99 9/1/99 Visa 456456456 Check AmEx 432432432 Cash Master Card1112223334 AmEx 332332332 326 327 3333 3684 9/1/99 FedEx 9/1/99 DHL Money Order Master Card122122321 329 330 4158 4175 9/1/99 Walk In 9/1/99 FedEx 331 333 5510 5926 336 5719 IS 257 – Fall 2012 1/1/01 2 1 11/8/00 4/4/00 9/11/00 8/12/00 12/10/99 4 3 4 1 1 1 6/27/00 2/7/00 5/9/00 10/10/00 3/15/00 3/15/00 11/9/99 2 4 2/10/00 3/10/00 2/17/00 Monterey 3/23/00 Florida 4000 24000 Cash Check 1 2 5/4/00 7/3/00 5/15/00 Cozumel 7/10/00 Florida 1571 6000 9/1/99 FedEx 9/1/99 DHL Money Order Discover 123123123 6 2 6/20/00 6/10/00 9/1/99 FedEx Cash 10 4/2/00 Walk In FedEx FedEx Walk In Emery Emery 12345 678 90 12/31/02 12/21/00 11/15/00 Fiji 4/18/00 Santa Barbara 10000 6000 7/11/00 2/14/00 5/16/00 10/17/00 4/12/00 4/12/00 8000 6000 20000 3000 8000 8000 Cozumel Monterey Fiji Santa Barbara New Jersey New Jersey 6/30/00 Santa Barbara 6/17/00 Fiji 36000 10000 4/24/00 Great Barrier Reef 200000 2011.09.06 - SLIDE 22 Line item = DIVEITEM Order No Item No 307 90010 307 90020 307 90021 307 90030 307 90051 310 90011 310 90045 310 90059 310 90074 310 90078 313 90127 314 90072 314 90094 314 90100 317 90012 IS 257 – Fall 2012 Rental/SaleQty Rental Rental Rental Rental Rental Rental Rental Rental Rental Rental Sale Rental Rental Rental Sale Line Note 4 1 1 2 2 1 1 1 1 1 1 3 3 3 2 This is our most popular mask. These are our best selling fins. A good weight belt for beginners Holds 10 cubic feet of cargo. 2011.09.06 - SLIDE 23 Shipping information = SHIPVIA Ship Via DHL Emery FedEx UPS US Mail IS 257 – Fall 2012 Ship Cost 8 11 12 10 6 2011.09.06 - SLIDE 24 Dive Equipment Stock= DIVESTOK Item No 90010 90011 90012 90020 90021 90022 90023 90024 90025 90030 90031 90032 90033 90040 90041 90042 IS 257 – Fall 2012 DescriptionEquipment On Class Hand Reorder Point Cost Sale Price Rental Price Shotgun 2 Snorkel - Clear 12 2 $18.00 $30.00 $2.00 Shotgun 2 Snorkel - Red 12 2 $18.00 $30.00 $2.00 Shotgun 2 Snorkel - Teal 11 2 $18.00 $30.00 $2.00 Tri-Vent Mask Mask - Clear 14 2 $62.50 $100.00 $5.00 Tri-Vent Mask Mask - Red 10 2 $62.50 $100.00 $5.00 Tri-Vent Mask Mask - Teal 14 2 $62.50 $100.00 $7.00 Quad Vision Mask Mask - Clear 11 2 $48.25 $80.00 $7.00 Quad Vision Mask Mask - Red 13 2 $48.25 $80.00 $7.00 Quad Vision Mask Mask - Teal 10 2 $48.25 $80.00 $10.00 Sea Wing Fins Fins - Clear 12 2 $60.00 $100.00 $12.00 Sea Wing Fins Fins - Red 11 2 $60.00 $100.00 $12.00 Sea Wing Fins Fins - Teal 12 2 $60.00 $100.00 $12.00 Jet Fin - Black Fins 14 2 $30.00 $60.00 $10.00 D350 Second Regulator Stage 11 1 $162.50 $270.00 $20.00 G250 Second Regulator Stage 13 1 $144.50 $240.00 $20.00 G200 Second Regulator Stage 12 1 $105.25 $175.00 $20.00 2011.09.06 - SLIDE 25 Dive Locations = DEST IS 257 – Fall 2012 2011.09.06 - SLIDE 26 Dive Sites = SITE IS 257 – Fall 2012 2011.09.06 - SLIDE 27 Sea Life = BIOLIFE IS 257 – Fall 2012 2011.09.06 - SLIDE 28 BIOSITE -- linking relation IS 257 – Fall 2012 2011.09.06 - SLIDE 29 Shipwrecks = SHIPWRK IS 257 – Fall 2012 2011.09.06 - SLIDE 30 Mapping to Other Models • Hierarchical – Need to make decisions about access paths • Network – Need to pre-specify all of the links and sets • Object-Oriented – What are the objects, datatypes, their methods and the access points for them • Object-Relational – Same as relational, but what new datatypes might be needed or useful (more on OR later) IS 257 – Fall 2012 2011.09.06 - SLIDE 31 Lecture Outline • Review • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 32 Normalization • Normalization theory is based on the observation that relations with certain properties are more effective in inserting, updating and deleting data than other sets of relations containing the same data • Normalization is a multi-step process beginning with an “unnormalized” relation – Hospital example from Atre, S. Data Base: Structured Techniques for Design, Performance, and Management. IS 257 – Fall 2012 2011.09.06 - SLIDE 33 Normal Forms • • • • • • First Normal Form (1NF) Second Normal Form (2NF) Third Normal Form (3NF) Boyce-Codd Normal Form (BCNF) Fourth Normal Form (4NF) Fifth Normal Form (5NF) IS 257 – Fall 2012 2011.09.06 - SLIDE 34 Normalization No transitive dependency between nonkey attributes All determinants are candidate keys - Single multivalued dependency IS 257 – Fall 2012 BoyceCodd and Higher Functional dependency of nonkey attributes on the primary key - Atomic values only Full Functional dependency of nonkey attributes on the primary key 2011.09.06 - SLIDE 35 Unnormalized Relations • First step in normalization is to convert the data into a two-dimensional table • In unnormalized relations data may repeat within a column IS 257 – Fall 2012 2011.09.06 - SLIDE 36 Unnormalized Relation Patient # Surgeon # 145 1111 311 Surg. date Jan 1, 1995; June 12, 1995 Patient Name John White Patient Addr 15 New St. New York, NY Surgeon Surgery Beth Little Michael Diamond Gallstone s removal; Kidney stones removal Postop drug Drug side effects Penicillin, none- rash none Tetracyclin e none Fever none Cephalosp orin none Demicillin none none none Eye Apr 5, 243 1234 467 1994 May 10, 1995 Mary Jones 10 Main St. Rye, NY Charles Field Cataract removal Patricia Gold Thrombos is removal Dogwood Lane 2345 189 Jan 8, 1996 Charles Brown Harrison, NY Open David Rosen Heart Surgery 55 Boston Post Road, 4876 145 Nov 5, 1995 Hal Kane 5123 145 May 10, 1995 Paul Kosher Apr 5, 1994 Dec 6845 243 IS 257 – Fall 2012 15, 1984 Ann Hood Chester, CN Blind Brook Mamaronec k, NY Hilton Road Larchmont, NY Beth Little Beth Little Cholecyst ectomy Gallstone s Removal Eye Cornea Replacem Charles ent Eye cataract Tetracyclin Field removal e Fever 2011.09.06 - SLIDE 37 First Normal Form • To move to First Normal Form a relation must contain only atomic values at each row and column. – No repeating groups – A column or set of columns is called a Candidate Key when its values can uniquely identify the row in the relation. IS 257 – Fall 2012 2011.09.06 - SLIDE 38 First Normal Form Pat ient # Surgeon # Surgery Date Pat ient Name Patient Addr Surgeon Name 15 New St. New York, 1111 145 01-Jan-95 John White 1111 311 12-Jun-95 John White 1234 243 05-Apr-94 Mary Jones 1234 467 10-May-95 Mary Jones 2345 4876 5123 189 145 145 08-Jan-96 05-Nov-95 10-May-95 NY 15 New St. New York, NY 10 Main St. Rye, NY 10 Main St. Rye, NY Dogwood Lane 6845 IS 257 – Fall 2012 243 243 05-Apr-94 15-Dec-84 Drug admin Side Effects G allstone Beth Litt le Michael Diamond s removal Kidney stones removal none none Charles Field Eye Cataract removal Tet racyclin e Fever Patricia Gold Thrombos is removal none none Penicillin rash O pen Charles Brown Harrison, NY David Rosen Heart Surgery Cephalosp orin none Hal Kane 55 Boston Post Road, Chester, CN Beth Litt le Cholecyst ectomy Demicillin none Paul Kosher Blind Brook Mamaronec k, NY Beth Litt le G allstone s Removal none none Eye Cornea Hilton Road 6845 Surgery Ann Hood Larchmont, NY Ann Hood Hilton Road Larchmont, NY Charles Field Replacem ent Tet racyclin e Fever Charles Field Eye cataract removal none none 2011.09.06 - SLIDE 39 1NF Storage Anomalies • Insertion: A new patient has not yet undergone surgery -- hence no surgeon # -- Since surgeon # is part of the key we can’t insert. • Insertion: If a surgeon is newly hired and hasn’t operated yet -- there will be no way to include that person in the database. • Update: If a patient comes in for a new procedure, and has moved, we need to change multiple address entries. • Deletion (type 1): Deleting a patient record may also delete all info about a surgeon. • Deletion (type 2): When there are functional dependencies (like side effects and drug) changing one item eliminates other information. IS 257 – Fall 2012 2011.09.06 - SLIDE 40 Second Normal Form • A relation is said to be in Second Normal Form when every nonkey attribute is fully functionally dependent on the primary key. – That is, every nonkey attribute needs the full primary key for unique identification IS 257 – Fall 2012 2011.09.06 - SLIDE 41 Second Normal Form Patient # 1111 1234 2345 4876 5123 6845 IS 257 – Fall 2012 Patient Name Patient Address 15 New St. New John White York, NY 10 Main St. Rye, Mary Jones NY Charles Dogwood Lane Brown Harrison, NY 55 Boston Post Hal Kane Road, Chester, Blind Brook Paul Kosher Mamaroneck, NY Hilton Road Ann Hood Larchmont, NY 2011.09.06 - SLIDE 42 Second Normal Form Surgeon # Surgeon Name 145 Beth Little 189 David Rosen 243 Charles Field 311 Michael Diamond 467 Patricia Gold IS 257 – Fall 2012 2011.09.06 - SLIDE 43 Second Normal Form Patient # Surgeon # Surgery Date 1111 1111 1234 1234 2345 4876 Drug Admin Side Effects 145 Gallstones 01-Jan-95 removal Kidney Penicillin rash 311 stones 12-Jun-95 removal none none 243 Eye Cataract 05-Apr-94 removal Tetracycline Fever 467 Thrombosis 10-May-95 removal 189 Open Heart 08-Jan-96 Surgery Cephalospori n none 145 Cholecystect 05-Nov-95 omy Demicillin none none none none none 5123 145 6845 243 6845 243 IS 257 – Fall 2012 Surgery Gallstones 10-May-95 Removal Eye cataract 15-Dec-84 removal Eye Cornea 05-Apr-94 Replacement none none Tetracycline Fever 2011.09.06 - SLIDE 44 1NF Storage Anomalies Removed • Insertion: Can now enter new patients without surgery. • Insertion: Can now enter Surgeons who haven’t operated. • Deletion (type 1): If Charles Brown dies the corresponding tuples from Patient and Surgery tables can be deleted without losing information on David Rosen. • Update: If John White comes in for third time, and has moved, we only need to change the Patient table IS 257 – Fall 2012 2011.09.06 - SLIDE 45 2NF Storage Anomalies • Insertion: Cannot enter the fact that a particular drug has a particular side effect unless it is given to a patient. • Deletion: If John White receives some other drug because of the penicillin rash, and a new drug and side effect are entered, we lose the information that penicillin can cause a rash • Update: If drug side effects change (a new formula) we have to update multiple occurrences of side effects. IS 257 – Fall 2012 2011.09.06 - SLIDE 46 Third Normal Form • A relation is said to be in Third Normal Form if there is no transitive functional dependency between nonkey attributes – When one nonkey attribute can be determined with one or more nonkey attributes there is said to be a transitive functional dependency. • The side effect column in the Surgery table is determined by the drug administered – Side effect is transitively functionally dependent on drug so Surgery is not 3NF IS 257 – Fall 2012 2011.09.06 - SLIDE 47 Third Normal Form Patient # Surgeon # Surgery Date IS 257 – Fall 2012 Surgery Drug Admin 1111 145 1111 311 01-Jan-95 Gallstones removal Kidney stones 12-Jun-95 removal 1234 243 05-Apr-94 Eye Cataract removal Tetracycline 1234 467 10-May-95 Thrombosis removal 2345 189 08-Jan-96 Open Heart Surgery Cephalosporin 4876 145 05-Nov-95 Cholecystectomy Demicillin 5123 145 10-May-95 Gallstones Removal none 6845 243 none 6845 243 15-Dec-84 Eye cataract removal Eye Cornea 05-Apr-94 Replacement Penicillin none none Tetracycline 2011.09.06 - SLIDE 48 Third Normal Form Drug Admin IS 257 – Fall 2012 Side Effects Cephalosporin none Demicillin none none none Penicillin rash Tetracycline Fever 2011.09.06 - SLIDE 49 2NF Storage Anomalies Removed • Insertion: We can now enter the fact that a particular drug has a particular side effect in the Drug relation. • Deletion: If John White recieves some other drug as a result of the rash from penicillin, but the information on penicillin and rash is maintained. • Update: The side effects for each drug appear only once. IS 257 – Fall 2012 2011.09.06 - SLIDE 50 Boyce-Codd Normal Form • Most 3NF relations are also BCNF relations. • A 3NF relation is NOT in BCNF if: – Candidate keys in the relation are composite keys (they are not single attributes) – There is more than one candidate key in the relation, and – The keys are not disjoint, that is, some attributes in the keys are common IS 257 – Fall 2012 2011.09.06 - SLIDE 51 Most 3NF Relations are also BCNF – Is this one? Patient # Patient Name Patient Address 15 New St. New 1111 John White York, NY 10 Main St. Rye, 1234 Mary Jones NY Charles Dogwood Lane 2345 Brown Harrison, NY 55 Boston Post 4876 Hal Kane Road, Chester, Blind Brook 5123 Paul Kosher Mamaroneck, NY Hilton Road 6845 Ann Hood Larchmont, NY IS 257 – Fall 2012 2011.09.06 - SLIDE 52 BCNF Relations Patient # IS 257 – Fall 2012 Patient Name Patient # 1111 John White 1111 1234 Mary Jones Charles 2345 Brown 1234 4876 Hal Kane 4876 5123 Paul Kosher 5123 6845 Ann Hood 6845 2345 Patient Address 15 New St. New York, NY 10 Main St. Rye, NY Dogwood Lane Harrison, NY 55 Boston Post Road, Chester, Blind Brook Mamaroneck, NY Hilton Road Larchmont, NY 2011.09.06 - SLIDE 53 Fourth Normal Form • Any relation is in Fourth Normal Form if it is BCNF and any multivalued dependencies are trivial • Eliminate non-trivial multivalued dependencies by projecting into simpler tables IS 257 – Fall 2012 2011.09.06 - SLIDE 54 Fifth Normal Form • A relation is in 5NF if every join dependency in the relation is implied by the keys of the relation • Implies that relations that have been decomposed in previous NF can be recombined via natural joins to recreate the original relation. IS 257 – Fall 2012 2011.09.06 - SLIDE 55 Effectiveness and Efficiency Issues for DBMS • Focus on the relational model • Any column in a relational database can be searched for values. • To improve efficiency indexes using storage structures such as BTrees and Hashing are used • But many useful functions are not indexable and require complete scans of the the database IS 257 – Fall 2012 2011.09.06 - SLIDE 56 Example: Text Fields • In conventional RDBMS, when a text field is indexed, only exact matching of the text field contents (or Greater-than and Lessthan). – Can search for individual words using pattern matching, but a full scan is required. • Text searching is still done best (and fastest) by specialized text search programs (Search Engines) that we will look at more later. IS 257 – Fall 2012 2011.09.06 - SLIDE 57 Normalization • Normalization is performed to reduce or eliminate Insertion, Deletion or Update anomalies. • However, a completely normalized database may not be the most efficient or effective implementation. • “Denormalization” is sometimes used to improve efficiency. IS 257 – Fall 2012 2011.09.06 - SLIDE 58 Normalizing to death • Normalization splits database information across multiple tables. • To retrieve complete information from a normalized database, the JOIN operation must be used. • JOIN tends to be expensive in terms of processing time, and very large joins are very expensive. IS 257 – Fall 2012 2011.09.06 - SLIDE 59 Downward Denormalization Customer ID Address Name Telephone Before: Order Order No Date Taken Date Dispatched Date Invoiced Cust ID IS 257 – Fall 2012 After: Customer ID Address Name Telephone Order Order No Date Taken Date Dispatched Date Invoiced Cust ID Cust Name 2011.09.06 - SLIDE 60 Upward Denormalization Order Order No Date Taken Date Dispatched Date Invoiced Cust ID Cust Name Order Item Order No Item No Item Price Num Ordered IS 257 – Fall 2012 Order Order No Date Taken Date Dispatched Date Invoiced Cust ID Cust Name Order Price Order Item Order No Item No Item Price Num Ordered 2011.09.06 - SLIDE 61 Denormalization • Usually driven by the need to improve query speed • Query speed is improved at the expense of more complex or problematic DML (Data manipulation language) for updates, deletions and insertions. IS 257 – Fall 2012 2011.09.06 - SLIDE 62 Using RDBMS to help normalize • Example database: Cookie • Database of books, libraries, publisher and holding information for a shared (union) catalog IS 257 – Fall 2012 2011.09.06 - SLIDE 63 Cookie relationships IS 257 – Fall 2012 2011.09.06 - SLIDE 64 Cookie BIBFILE relation ACCNO A003 T082 C024 B006 B007 B005 B008 B010 B009 B012 B011 B014 B013 B016 B017 F047 B116 S102 B118 B018 C031 C032 C034 AUTHOR TITLE LOC PUBID DATE AMERICAN LIBRARY ASSOCIATION ALA BULLETIN CHICAGO 04 ANDERSON, THEODORE THE TEACHING OF MODERN PARIS LANGUAGES53 1955 AXT, RICHARD G. COLLEGE SELF STUDYBOULDER, : LECTURES CO.ON INSTITU 51 1960 BALDERSTON, FREDERICKMANAGING E. TODAYS UNIVERSITY SAN FRANCISCO 27 1975 BARZUN, JACQUES TEACHER IN AMERICA GARDEN CITY 18 1954 BARZUN, JACQUES THE AMERICAN UNIVERSITY NEW YORK : HOW IT RUNS, 24 W 1970 BARZUN, JACQUES THE HOUSE OF INTELLECT NEW YORK 24 1961 BELL, DANIEL THE COMING OF POST-INDUSTRIAL NEW YORK SOCIETY 09 : 1976 BENSON, CHARLES S. IMPLEMENTING THE LEARNING SAN FRANCISCO SOCIETY 27 1974 BERG, IVAR EDUCATION AND JOBSBOSTON : THE GREAT TRAINING 10 1971 BERSI, ROBERT M. RESTRUCTURING THE BACCALAUREATE WASHINGTON, D.C.03 1973 BEVERIDGE, WILLIAM I. THE ART OF SCIENTIFIC NEW INVESTIGATION YORK 58 1957 BIRD, CAROLINE THE CASE AGAINST COLLEGE NEW YORK 08 1975 BISSELL, CLAUDE T. THE STRENGTH OF THE TORONTO UNIVERSITY 57 1968 BLAIR, GLENN MYERS EDUCATIONAL PSYCHOLOGY NEW YORK 30 1962 BLAKE, ELIAS, JR. THE FUTURE OF THE BLACK CAMBRIDGE, COLLEGES MA. 02 1971 BOLAND, R.J. CRITICAL ISSUES IN INFORMATION CHICHESTER, SYSTEMS ENG.63 R 1987 BROWN, SANBORN C., ED. SCIENTIFIC MANPOWER CAMBRIDGE, MASS. 29 1971 BUCKLAND, MICHAEL K. LIBRARY SERVICES IN ELMSFORD, THEORY ANDNY CONTEXT 70 1983 BUDIG, GENE A. ACADEMIC QUICKSANDLINCOLN, : SOME NEBRASKA TRENDS AND 37 ISS 1973 CALIFORNIA. DEPT. OF JUSTICE LAW IN THE SCHOOL MONTCLAIR, N.J. 35 1974 CAMPBELL, MARGARET A.WHY WOULD A GIRL GO OLD INTO WESTBURY, MEDICINE? N.Y. 48 1973 CARNEGIE COMMISSION ON A DIGEST HIGHER OF REPORTS NEW OF YORK THE CARNEGIE 30 COMM 1974 IS 257 – Fall 2012 PRICE $3.00 $10.95 $7.00 $6.00 $7.00 $5.00 $8.00 $10.00 $9.00 $12.00 $11.00 $14.00 $13.00 $14.00 $11.00 $14.25 $30.95 $4.00 $12.00 $13.00 $0.50 $1.50 $3.50 PAGINATION ILL 63 V. ILL. 294 P. X, 300 P. GRAPHS XVI, 307 P. 280 P. XII, 319 P. VIII, 271 P. XXVII, 507 P. XVII, 147 P. XX, 200 P. IV, 160P. XIV, 239 P. XII, 308 P. VII, 251 P. 678 P. VIII, PP. 539 XV, 394 P. ILL. X, 180 P. XII, 201 P. ILL. 74 P. IV, 87 P. V, 114 P. 399 P. HEIGHT 26 22 28 24 18 20 21 21 24 21 23 18 18 21 24 23 24 26 23 23 21 24 24 2011.09.06 - SLIDE 65 How to Normalize? • Currently no way to have multiple authors for a given book, and there is duplicate data spread over the BIBFILE table • Can we use the DBMS to help us normalize? • It is possible (but takes a bit more SQL knowledge than has been hinted at so far) – We will return to this problem later – But CONCEPTUALLY… IS 257 – Fall 2012 2011.09.06 - SLIDE 66 Using RDBMS to Normalize Create a new table for Authors that includes author name and an automatically incrementing id number (for primary key) Populate the table using the unique author names (which get assigned id numbers) by extracting them from the BIBFILE Create a new table containing a author_id and an ACCNO Populate the new table by matching the Authors and BIBFILE names Drop the Author name column from BIBFILE IS 257 – Fall 2012 2011.09.06 - SLIDE 67 Lecture Outline • Review • Logical Model for the Diveshop database • Normalization • Relational Advantages and Disadvantages IS 257 – Fall 2012 2011.09.06 - SLIDE 68 Advantages of RDBMS • Relational Database Management Systems (RDBMS) • Possible to design complex data storage and retrieval systems with ease (and without conventional programming). • Support for ACID transactions – Atomic – Consistent – Independent – Durable IS 257 – Fall 2012 2011.09.06 - SLIDE 69 Advantages of RDBMS • Support for very large databases • Automatic optimization of searching (when possible) • RDBMS have a simple view of the database that conforms to much of the data used in business • Standard query language (SQL) IS 257 – Fall 2012 2011.09.06 - SLIDE 70 Disadvantages of RDBMS • Until recently, no real support for complex objects such as documents, video, images, spatial or time-series data. (ORDBMS add -- or make available support for these) • Often poor support for storage of complex objects from OOP languages (Disassembling the car to park it in the garage) • Usually no efficient and effective integrated support for things like text searching within fields (MySQL does have simple keyword searching now with index support) IS 257 – Fall 2012 2011.09.06 - SLIDE 71 Next Week • (Re)Introduction to SQL • More on Logical Design/Normalization • Physical Design IS 257 – Fall 2012 2011.09.06 - SLIDE 72