Database DesignPowerPoint PresentationSlide 3Infinite Relational DatabasesThe View LevelSlide 6Slide 7The Logical LevelSlide 9Example (1)Example (2)Relation schemes & Instances (1)Relation schemes & Instances (2)Infinite Relational Data ModelTemporal & Spatial DataTemporal Data Type (1)Temporal DatabasesSpatiotemporalAbstract Data Types (1)Abstract Data Types (2)Discussion QuestionsQuestions for the Next LectureTasks for Next Lecture2003SJSU -- CmpE L1-S1 Infinite R-DBDatabase Design Dr. M.E. Fayad, ProfessorComputer Engineering Department, Room #283I College of EngineeringSan José State UniversityOne Washington SquareSan José, CA 95192-0180 http://www.engr.sjsu.edu/~fayad2003SJSU – CmpE --- M.E. Fayad L1-S2 Infinite R-DB2Lesson 1:Infinite Relational Database2003SJSU – CmpE --- M.E. Fayad L1-S3 Infinite R-DB Lesson ObjectivesObjectives3 Understand Infinite Relational Databases Explore the view level Understand the logical view Abstract Data Type2003SJSU – CmpE --- M.E. Fayad L1-S4 Infinite R-DBData Abstraction- allows people to forget unimportant details–View Level – a way of presenting data to a–group of users–Logical Level – how data is understood to be when writing queries4Infinite Relational Databases2003SJSU – CmpE --- M.E. Fayad L1-S5 Infinite R-DBThe highest level of data abstraction is the view levelA view is a way of presenting data to a particular group of users.Data Presentation may depend on users preferences.Each view has to be functional for the users.This means that when designing a view we must keep in mind the functions to be preformed on the data.5The View Level2003SJSU – CmpE --- M.E. Fayad L1-S6 Infinite R-DBView level presentation of the data: Science, Art, or both (discussion)We will illustrate examples from different computer fields, such as computer graphics, for view level presentation of complex data, especially spatiotemporal data, such as realistic display of images and movies.6The View Level2003SJSU – CmpE --- M.E. Fayad L1-S7 Infinite R-DBExamples:–Charts –Graphs–Drawings–Maps–Video or Animation7The View LevelExamples?What is a view?What is a model?What are the differences between a model and a view?2003SJSU – CmpE --- M.E. Fayad L1-S8 Infinite R-DBExample: Infinite relational data model•Relation – table(Each table has a name and defines a relation)•Relational scheme – top row / list of attributes(The top row of a table is called an attribute name)(The ordered set of attributes of a table is called a relation scheme.)•Arity or dimension – number of attributes of a relation(We will use arity and dimension interchangeably with a preference for dimension in the case of spatiotemporal relations.)8The Logical Level2003SJSU – CmpE --- M.E. Fayad L1-S9 Infinite R-DBExample: Infinite relational data model•Database schema – set of relation names and schemes•Tuple / Point – each row below the scheme(we will use these two terms interchangeably with a preference for point in the case of spatiotemporal relations.•Instance – the set of tuples in a table(Each row describes an instance of the scheme.)(Please remember a relation schemes are usually fixed while a relation instances may change over time due to database updates.)9The Logical Level2003SJSU – CmpE --- M.E. Fayad L1-S10 Infinite R-DB10Example (1)SSN Surname First Name(s) Telephone Number123-45-6789 Doe J ane Q. 512-555-1234987-65-4321 Fulano J uan 210-543-9876567-89-0123 Roe Richard Rodney 512-987-6431SSN Wages Interest Capital Gain123-45-6789 100,000 3,400 0987-65-4321 83,640 2,821 3,400567-89-0123 46,000 501 1,2002003SJSU – CmpE --- M.E. Fayad L1-S11 Infinite R-DBName the relations!What is arity of each relation?What is the relation scheme of each relation?What is the database scheme?How many tupls in each of the relation?How many instances of each of these relations?11Example (2)2003SJSU – CmpE --- M.E. Fayad L1-S12 Infinite R-DBRelation schemes are usually fixedRelation instances change with updatesExample Scheme:Taxrecord(SSN,Wages,Interest,Capital_gain)Taxtable(Income,Tax)12Relation schemes & Instances (1)2003SJSU – CmpE --- M.E. Fayad L1-S13 Infinite R-DBExample: Streets(Name, X, Y )Streets contains pairs of street names and (x,y) points such that the point belongs to the street. There are an infinite number of (x, y) locations associated with each street. Example: Crops(Corn,Rye,Sunflower, Wheat) Crops contains all possible combinations of four crops that a farmer could plant. There are an infinite number of tuples in any instance of this relation.Relation schemes & Instances (2)2003SJSU – CmpE --- M.E. Fayad L1-S14 Infinite R-DBOther examples: Temporal Data Spatial Data Operations Research14Infinite Relational Data Model2003SJSU – CmpE --- M.E. Fayad L1-S15 Infinite R-DBIn many application areas of machine learning and data mining, researchers face challenges entailed by temporal and spatial data.What are the differences between temporal and spatial data?15Temporal & Spatial Data2003SJSU – CmpE --- M.E. Fayad L1-S16 Infinite R-DB16Temporal Data Type (1)The user-defined temporal data type is a time representation specially designed to meet the specific needs of the user. For example, the designers of a database used for class scheduling in a school might be based on a "Year:Term:Day:Period" format. Terms belonging to a user-defined temporal data type get the same query language support as do terms belonging to built-in temporal data types such as the DATE data type.2003SJSU – CmpE --- M.E. Fayad L1-S17 Infinite R-DBA temporal database is a database that supports some aspect of time, not counting user-defined time. 17Temporal Databases2003SJSU – CmpE --- M.E. Fayad L1-S18 Infinite R-DBThe spatiotemporal is used to indicate that the modified concept concerns simultaneous support of some aspect of time and some aspect of space, in one or more dimensions.18Spatiotemporal2003SJSU – CmpE --- M.E. Fayad L1-S19 Infinite R-DBDomain – range of values for an attribute.– string, integers or real numbersScalar Domain – always a single value – (ex: string, integer or real
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