Course organisation TDDC94 Database Technology TDDI60 Technical Databases Responsible:
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Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Lena Strömbäck lestr@ida.liu.se IISLAB IDA TDDC94 Database Technology TDDI60 Technical Databases Course organisation • 12 lectures (TDDI60 8 lectures) • Written exam • Lab exercises - Lena Strömbäck 3 computer labs 1 paper lab Mini project http://www.ida.liu.se/~TDDC94 augusti 2007 1 1 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Examiner: • One group have two rooms. Paper lab scheduled in lecture rooms. • • Teachers: Lena Strömbäck, lestr@ida.liu.se Tommy Ellkvist, g-tomel@ida.liu.se Almut Herzog, almhe@ida.liu.se José M Pená, jmp@ida.liu.se 3 3 augusti 2007 4 4 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Laboratory information • You need a special database account automatically created at course registration e-mail system@ida.liu.se if any problems Handing in labs • Each lab requires a written report • Labs can be handed in: • • 5 5 augusti 2007 6 To the teacher at the lab At IDAs postboxes, opposite to Café Java Labs can be fetched: Subscribe for labs via course home page Choose your course code (TDDC94, TDDI60) Use groups A and B as far as possible OLD-gr, discuss with Lena before choosing this group augusti 2007 Mini-project: Less supervision. Katarina Löfstrand, katlo@ida.liu.se Director of studies: Lab schedule on the course web-page. He Tan, hetan@ida.liu.se • Lena Strömbäck lestr@ida.liu.se IISLAB IDA • Lena Strömbäck, lestr@ida.liu.se Course administration: augusti 2007 Laboratory schedule Course leader and Course assistant • 2 2 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Course leadership • augusti 2007 From the teacher at the lab At the OUT box outside each teachers office Remember to fetch your labs, it is your only proof that you have passed the labs. 6 1 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Labs reports deadlines • Lab reports are handed in: augusti 2007 • Last day for handing in: Oct 14th • Next occasions: Jan 10th, August 2007 • Later: Redo the labs!!! Two parts: • • 8 Elmasri, R., Navathe, S., Fundamentals of Database Systems, 5th edition, Addison-Wesley, ISBN 0-32148506-X, 2006 Course overview – Part1 • Introduction and ER-modeling (Lena) • The Relational Model (José) • SQL (José) • EER and mapping ER/EER to relational, Intro to transactions (José) • Lab compendium: Databases, ADIT-1, version autumn 2006 9 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Functional dependencies and normalization (Almut) SQLPSM, triggers and stored procedures (José) Mini-project implementation • Data structures for databases (He) • Data Structures for Databases II (NOT TDDI60) (He) • Transactions and Concurrency Control (NOT TDDI60) (Almut) • Database Recovery (NOT TDDI60) (Almut) • Query Processing and Optimization (NOT TDDI60) (Almut) • Summary and Outlook; (Lena) augusti 2007 11 Lab3: Normalization Lab4: Stored Procedures 10 10 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Course overview - Part 2 • augusti 2007 Lab2: Database Design and ER/modeling Start with modeling part of the mini project! • 9 Lab1: SQL-queries and view • augusti 2007 Studentportalen Last date: 2006-10-03 8 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Course literature Dictionary – not electronic No calculator No books allowed Registration to the exam augusti 2007 Theoretical and practical Have to pass both parts For TDDI60: Some theoretical questions Equipment 7 • Written exam • Lab1: Week 35 Lab2: Week 36 Lab3: Week 37 Lab4: Week 38 Project: Model Week 37 Project: Implementation Week 41 7 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Lena Strömbäck lestr@ida.liu.se IISLAB IDA Today´s lecture • Database introduction and terminology • EER-modelling Mandatory occasion on modeling sept 21st 11 augusti 2007 12 12 2 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA augusti 2007 What is a database? One way to store data in electronic format. • • Used in ordinary life, banks, booking of hotels or travels, search in the library, shopping. A database represents some aspect of the real world, i.e. a mini world. • • New applications: multimedia databases, geographical information systems, real time databases A database consists of a logical coherent collection of data with an underlying meaning. • A database is designed, built and filled with data with respect to an underlying purpose. 13 13 File storage: 223344-5566PELLE PERSSON STIGSTIGEN 11 334455-6677ANNA ANDSSON augusti 2007 GATGATAN 3 LINDESBERG 17 augusti 2007 • Flat files not a good way for storing complex data. Not flexible. (Solution data modelling) • Inefficiency when replacing hard- or software. (Solution data independence) • Problems with handling many users that want to change the data. (Solution transactions) • Users might want to see and have access to different parts of the data. (Solution views) • Data should be persistent over time. (Solution recovery) • Efficient storage of large quantities of data. (Solution indexing) Hierarchical databases 17 augusti 2007 16 16 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Early database models: • Problems with file storage ÖREBRO 15 Network databases 14 14 KLARKÖPING 15 • augusti 2007 Lena Strömbäck lestr@ida.liu.se IISLAB IDA 112233-4455KALLE KARLSSON VÄGVÄGEN 13 Lena Strömbäck lestr@ida.liu.se IISLAB IDA What is a database? - Definition • Lena Strömbäck lestr@ida.liu.se IISLAB IDA augusti 2007 Lena Strömbäck lestr@ida.liu.se IISLAB IDA 18 70:s The relational model • Data stored as tables. • Theoretical model. • Standardised query language. • In the beginning these kind of databases where slow. Hierarchical databases faster. 18 3 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Lena Strömbäck lestr@ida.liu.se IISLAB IDA More recent databases • Object oriented databases (80:s) - model: persistent objects, messages, encapsulation, inheritance augusti 2007 Object-relational databases (90:s) • XML-databases (00:s) 19 19 Lena Strömbäck lestr@ida.liu.se IISLAB IDA augusti 2007 • Databases • database management system (DBMS): A number of programs that allows a user to create and support a database • database system = database + database management system • Relational databases dominating. • Hierarchical databases still in use. (Mainly in flight industry.) • Object-oriented databases in use, especially as objectrelational databases. • XML-databases – new, first commercial products appearing. 20 20 Lena Strömbäck lestr@ida.liu.se IISLAB IDA DBMS - benefits 21 21 Lena Strömbäck lestr@ida.liu.se IISLAB IDA augusti 2007 Today: augusti 2007 22 22 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Architecture - three levels of data Control of redundant information Data access Persistent data storage Allow questions and inference Allow several users Representation of complex data relations Efficient storage of data Integrity Constraints Backup and recovery. Handling many users Pelle Data independence between the levels Sums total salary costs View View View Kalle Conceptual level Updates the salary for 1000 employees Database Physical level augusti 2007 23 23 augusti 2007 24 24 4 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Lena Strömbäck lestr@ida.liu.se IISLAB IDA Persistency and errors Power failure Course goals (1) • Understand the important concepts within databases and database terminology • Design a database for a given application • Design and use a relational database Kalle Updates the salary for 1000 employees augusti 2007 25 26 26 Theoretical foundations behind relational databases • augusti 2007 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Course goals (2) • Course goals (3) • Relational algebra How these have impact on database implementation (Only TDDB38) Query optimisation (Only TDDB38) Understand how databases can support multiple users Understand how the database is stored on the computer Concept of relations Use SQL Use MySQL Decipher a new relational database system Database 25 Lena Strömbäck lestr@ida.liu.se IISLAB IDA EER-modelling Basic technology, file structures, indexing Impact on database performance B-Trees, Hashing (Only TDDB38) • What problems occur Views Transactions Serialisation (only TDDB38) Understand how persistency can be guaranteed. (only TDDB38) Recovery augusti 2007 27 27 augusti 2007 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Databases 28 28 ER modelling User 4 Real World Model Updates UserQueries 3 Answers Updates UserQueries 2 Answers UserQueries 1 Answers Updates Updates Queries Answers Personal number Address Database Database management system Processing of queries and updates Name Access to stored data E-mail Telephone Age Physical database augusti 2007 30 30 5 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA ER diagrams Candidate keys Attribute • A conceptual model • A structured way of modelling data. • Independent of database type. • Documentation of your structure. E-mail E-mail Composite attributes PNummer Entity GName Employee Name FName Age Free Multiple valued attribute Derived attribute augusti 2007 31 31 Relations Total participation Pnum Dnum Employee Employed at Department Dnum Pnum Employed at Employee Department “Every department must have at least one employee” “Employees are employed at departments” Total participation Cardinalities Pnum Dnum Pnum Dnum N Employee Employed at Department “Every employee must belong to a department” Employee Employed at 1 Department “Each department have many employees, but each employee can only belong to one department” 6 Responsible: 2000-01-26 Cardinalities Cardinalities Pnum Dnum 1 N Employed at Employee Pnum N Department Dnum (1,1) Employed at (1,100) Pnum Employee Employed at 1 Department “Employees are identified through their departments, i.e. Salesman John” Lena Strömbäck lestr@ida.liu.se IISLAB IDA ER-example 1 Persons lives at an address. 41 Dnum N Department “Each department have up to 100 employees, but each employee can only belong to one department” augusti 2007 Department Weak entities Pnum M “Each department have many employees, and each employee can belong to many departments” Cardinalities Lena Strömbäck lestr@ida.liu.se IISLAB IDA Employed at Employee “Each department have one employee, but each employee can belong to many departments” Employee Dnum ER-example 2 Books are written by one or more authors. Are addresses important in the database? Are authors important in the database? Can you talk about the author without mentioning the book? 41 augusti 2007 42 42 7 Responsible: 2000-01-26 Lena Strömbäck lestr@ida.liu.se IISLAB IDA Lena Strömbäck lestr@ida.liu.se IISLAB IDA ER-example 3 ER Example 4: Customers can rent video films. Students take courses and study at study programs with different length. A study program consists of a set of courses. Students are identified by their e-mail address. A course is identified by its course code and the student earn a number of points when they have taken the course. Is the rental history important? Can the same video be rented more than once? augusti 2007 43 43 Lena Strömbäck lestr@ida.liu.se IISLAB IDA augusti 2007 44 44 EER-modelling • Adding inheritance to ER-diagrams Technichian ENumber Teleph. Spec. Lang. Salary ENumber augusti 2007 Administrator Teleph. Salary 45 45 ENumber Employee Employee Salary Teleph. d Technician ENumber Teleph. d Spec. Administrator Salary ENumber Technician Lang. ENumber Teleph. Salary Teleph. Spec. Administrator Lang. Salary ENumber Teleph. Salary 8 Responsible: 2000-01-26 Disjoint inheritance Full participation ENumber ENumber Employee Employee Salary Teleph. d Technician Spec. d Administrator Lang. Technician Spec. Overlapping inheritance Multiple inheritance ENumber ENumber Employee Spec. Salary Teleph. o Technician Lang. Employee Salary Teleph Administrator “All employees must be either a technician or an administrator” “Employees can be either technicians (x)or administrators” o Administrator Lang. “There are employees that are both technicians and administrators” Lena Strömbäck lestr@ida.liu.se IISLAB IDA Salary Teleph. Technician Spec. AdmTechn Administrator Lang. Procent Example 2: At the university there are two kinds of students, graduate and undergraduate Dependent on which category a student belong, a different set of courses are available. Some courses are available only for graduate students, some only for undergraduate and some for all students. augusti 2007 53 53 9
