Michael Emmerich Leiden Institute for Advanced Computer Science, Leiden University pptx

Preliminaries Introductory example Overview of the course Historical development of databases Databases Introduction Michael Emmerich Leiden Institute for Advanced Computer Science, Leiden University January 17, 2012 Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Database people dr Michael Emmerich - Assistant Professor (emmerich@liacs.nl) drs Hossein Rahmani - PhD Student drs Martin Wimmers - Master Student N.N - Master Student our email: databases@liacs.nl Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Course regulations, grades Assignment 1: Basics and Practice: Modeling and SQL DML and DDL Assignment 2: Advanced Topics: XML, Query Optimization, Transactions, Schema Refinement Exam (June, August) Final Grade = 0.2 * First Assignment + 0.2 * Second Assignment + 0.6 Exam Assignments can be done in pairs, but also alone Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Further info Book: Database Management Systems: Raghu Ramakrishnan, Jochen Gehrke, McGraw Hill, Third Edition our webpage: www.liacs.nl/databases Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases What is a database? What is a database? Do you know examples? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases What is a database? What is a database? Do you know examples? Database = A character in ’The simpsons’ Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases What is a database? What is a database? Do you know examples? Database = a collection of data pieces and meta-information (schema) on how this data is organized Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases What is a database? What is a database? Do you know examples? Database = a collection of data pieces and meta-information (schema) on how this data is organized Database Management System = software used to manage the database Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases How to organize address data? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Where to store adresses (head, paper, tape (Datasette), harddisk(s), internet server, USB-stick, )? What we want to store in a record (first name, second name, street, telephone)? Which informations we may consider for the future (e.g email, birthday, bankaccount, webpage, ip, image, holographic picture, etc )? By means of which information should we sort the data and identify data records? How can we deal with more complex data? (e.g relations between persons: A knows B, B is married to C)? How can we ensure consistency and avoid redundant storage? How can we make sure that nobody reads our addresses? How can many people edit the address database concurrently from the internet? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Overview of the course (1) Basics Data modeling - how to describe the organization of data with ER-Diagrams? Relational model - how to use tables to store data? how to translate ER diagrams to SQL? SQL DDL - how to define data in a databases? SQL Queries - how to retrieve data from a database and program constraints and triggers? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Overview of the course (2) Application programming Embedded SQL - how to call databases from C++ programs? JDBC - how to build database-backed internet applications? Large Objects - how to maintain pictures, sounds, etc in Databases? Excursion: XML - an alternative way to build databases Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Overview of the course (3) Theoretical aspects and distributed databases Algebra and calculus - how to reason formally about SQL queries? Query optimization and indexes - how to make data access efficient? Schema refinement - how to minimize redundancy? Transaction management - how to ensure consistency if many people use database at the same time? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Overview of the course (4) Advanced topics ( if time is left) Data-Mining - how to obtain patterns and knowledge in large databases? ProLog - how to allow for more difficult queries in systems combining rules and facts? Data-warehousing - how to build systems that integrate several databases? your choice? Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases From ancient to modern Origins are non-electronical: Oral tradition, stone-plates, books, libraries, microfiche, etc not to be ingnored, many concepts/principles developed then - look at town library’s organization! often hierarchical sorting of information (efficient access in logarithmic time) Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases The early days 1960s: Computers become available for companies First database systems store data sequentially on punch cards Two main data-models emerge - network model (CODASYL) and hierarchical model (IBM) are developed Emphasize is on the physical organization and direct access of the data Change of data organization and record structure requires complete rewrite Data and programs get separated SABRE system by IBM and American Airlines is developed as a major application Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Towards the relational model Edgar Codd Larry Ellison Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Towards the relational model E F Codd (to that time employee at IBM) proposed relational database model - e.g using tables with a schema to organize data The relational model disconnects the data (physical storage method) from its schema (logical organization) This system has been standard since First implementation of relational model by Berkeley University: Ingres First commercial exploitation of relational model by Larry Ellisons Relational Software Inc called Oracle V2 introduces Structured Query Language (SQL) IBM sticks long time with hierarchical models, and much later introduces System R Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Conceptual data models The conceptual model is a high level, often graphical, description of data In database design conceptual models are mapped to logical models which are mapped to physical description of data Peter Pin-Chan Chen (1976) introduced Entity-Relationship model (ER-model) as an universal graphical language to describe data Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Further evolution of databases 80ties: SQL develops and becomes standard New produts: Sybase, Paradox, Dbase-III (later FoxPro), System R/R+, IBM-DB2, Watcom SQL, etc Simple databases for personal computer arise, such as Excel/Access 1990ties: The internet emerges and with it web-based database technology Transaction processing and distributed DBMS gain importance Multimedia databases emerge large scale , often participatory, internet applications based on gigantic databases emerge (EBAY, Google*, Wikipedia, researchindex etc etc.) new, open, data formats and models are discussed: WikiMedia, XML etc Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases Server-Farms Figure: A server-farm for a database-backed internet application Michael T M Emmerich Databases ... people dr Michael Emmerich - Assistant Professor (emmerich@ liacs.nl) drs Hossein Rahmani - PhD Student drs Martin Wimmers - Master Student N.N - Master Student our email: databases@liacs.nl Michael. .. www.liacs.nl/databases Michael T M Emmerich Databases Preliminaries Introductory example Overview of the course Historical development of databases What is a database? What is a database? Do you know examples? Michael. .. know examples? Database = a collection of data pieces and meta-information (schema) on how this data is organized Michael T M Emmerich Databases Preliminaries Introductory example Overview of