Future of Database Systems University of California, Berkeley School of Information Management and Systems SIMS 257: Database Management IS 257 – Fall 2005 2005.11.21 - SLIDE 1 Lecture Outline • Review – Applications for Data Warehouses – Data Mining • Thanks again to lecture notes from Joachim Hammer of the University of Florida • Future of Database Systems • Predicting the future… • Quotes from Leon Kappelman “The future is ours” CACM, March 2001 • Accomplishments of database research over the past 30 years • Next-Generation Databases and the Future IS 257 – Fall 2005 2005.11.21 - SLIDE 2 Lecture Outline • Review – Applications for Data Warehouses – Data Mining • Thanks again to lecture notes from Joachim Hammer of the University of Florida • Future of Database Systems • Predicting the future… • Quotes from Leon Kappelman “The future is ours” CACM, March 2001 • Accomplishments of database research over the past 30 years • Next-Generation Databases and the Future IS 257 – Fall 2005 2005.11.21 - SLIDE 3 What is Decision Support? • Technology that will help managers and planners make decisions regarding the organization and its operations based on data in the Data Warehouse. – What was the last two years of sales volume for each product by state and city? – What effects will a 5% price discount have on our future income for product X? • Increasing common term is KDD – Knowledge Discovery in Databases IS 257 – Fall 2005 2005.11.21 - SLIDE 4 Conventional Query Tools • Ad-hoc queries and reports using conventional database tools – E.g. Access queries. • Typical database designs include fixed sets of reports and queries to support them – The end-user is often not given the ability to do ad-hoc queries IS 257 – Fall 2005 2005.11.21 - SLIDE 5 OLAP • Online Line Analytical Processing – Intended to provide multidimensional views of the data – I.e., the “Data Cube” – The PivotTables in MS Excel are examples of OLAP tools IS 257 – Fall 2005 2005.11.21 - SLIDE 6 Data Cube IS 257 – Fall 2005 2005.11.21 - SLIDE 7 Operations on Data Cubes • Slicing the cube – Extracts a 2d table from the multidimensional data cube – Example… • Drill-Down – Analyzing a given set of data at a finer level of detail IS 257 – Fall 2005 2005.11.21 - SLIDE 8 Star Schema • Typical design for the derived layer of a Data Warehouse or Mart for Decision Support – Particularly suited to ad-hoc queries – Dimensional data separate from fact or event data • Fact tables contain factual or quantitative data about the business • Dimension tables hold data about the subjects of the business • Typically there is one Fact table with multiple dimension tables IS 257 – Fall 2005 2005.11.21 - SLIDE 9 Star Schema for multidimensional data Order OrderNo OrderDate … Customer CustomerName CustomerAddress City … Salesperson SalespersonID SalespersonName City Quota IS 257 – Fall 2005 Fact Table OrderNo Salespersonid Customerno ProdNo Datekey Cityname Quantity TotalPrice Product ProdNo ProdName Category Description … City CityName State Country … Date DateKey Day Month Year … 2005.11.21 - SLIDE 10 Data Mining • Data mining is knowledge discovery rather than question answering – May have no pre-formulated questions – Derived from • Traditional Statistics • Artificial intelligence • Computer graphics (visualization) IS 257 – Fall 2005 2005.11.21 - SLIDE 11 Goals of Data Mining • Explanatory – Explain some observed event or situation • Why have the sales of SUVs increased in California but not in Oregon? • Confirmatory – To confirm a hypothesis • Whether 2-income families are more likely to buy family medical coverage • Exploratory – To analyze data for new or unexpected relationships • What spending patterns seem to indicate credit card fraud? IS 257 – Fall 2005 2005.11.21 - SLIDE 12 Data Mining Applications • • • • • • Profiling Populations Analysis of business trends Target marketing Usage Analysis Campaign effectiveness Product affinity IS 257 – Fall 2005 2005.11.21 - SLIDE 13 Data Mining Algorithms • • • • • Market Basket Analysis Memory-based reasoning Cluster detection Link analysis Decision trees and rule induction algorithms • Neural Networks • Genetic algorithms IS 257 – Fall 2005 2005.11.21 - SLIDE 14 Market Basket Analysis • A type of clustering used to predict purchase patterns. • Identify the products likely to be purchased in conjunction with other products – E.g., the famous (and apocryphal) story that men who buy diapers on Friday nights also buy beer. IS 257 – Fall 2005 2005.11.21 - SLIDE 15 Memory-based reasoning • Use known instances of a model to make predictions about unknown instances. • Could be used for sales forcasting or fraud detection by working from known cases to predict new cases IS 257 – Fall 2005 2005.11.21 - SLIDE 16 Cluster detection • Finds data records that are similar to each other. • K-nearest neighbors (where K represents the mathematical distance to the nearest similar record) is an example of one clustering algorithm IS 257 – Fall 2005 2005.11.21 - SLIDE 17 Link analysis • Follows relationships between records to discover patterns • Link analysis can provide the basis for various affinity marketing programs • Similar to Markov transition analysis methods where probabilities are calculated for each observed transition. IS 257 – Fall 2005 2005.11.21 - SLIDE 18 Decision trees and rule induction algorithms • Pulls rules out of a mass of data using classification and regression trees (CART) or Chi-Square automatic interaction detectors (CHAID) • These algorithms produce explicit rules, which make understanding the results simpler IS 257 – Fall 2005 2005.11.21 - SLIDE 19 Neural Networks • Attempt to model neurons in the brain • Learn from a training set and then can be used to detect patterns inherent in that training set • Neural nets are effective when the data is shapeless and lacking any apparent patterns • May be hard to understand results IS 257 – Fall 2005 2005.11.21 - SLIDE 20 Genetic algorithms • Imitate natural selection processes to evolve models using – Selection – Crossover – Mutation • Each new generation inherits traits from the previous ones until only the most predictive survive. IS 257 – Fall 2005 2005.11.21 - SLIDE 21 Lecture Outline • Review – Applications for Data Warehouses – Data Mining • Thanks again to lecture notes from Joachim Hammer of the University of Florida • Future of Database Systems • Predicting the future… • Quotes from Leon Kappelman “The future is ours” CACM, March 2001 • Accomplishments of database research over the past 30 years • Next-Generation Databases and the Future IS 257 – Fall 2005 2005.11.21 - SLIDE 22 • Radio has no future, Heavier-than-air flying machines are impossible. X-rays will prove to be a hoax. – William Thompson (Lord Kelvin), 1899 IS 257 – Fall 2005 2005.11.21 - SLIDE 23 • This “Telephone” has too many shortcomings to be seriously considered as a means of communication. The device is inherently of no value to us. – Western Union, Internal Memo, 1876 IS 257 – Fall 2005 2005.11.21 - SLIDE 24 • I think there is a world market for maybe five computers – Thomas Watson, Chair of IBM, 1943 IS 257 – Fall 2005 2005.11.21 - SLIDE 25 • The problem with television is that the people must sit and keep their eyes glued on the screen; the average American family hasn’t time for it. – New York Times, 1949 IS 257 – Fall 2005 2005.11.21 - SLIDE 26 • Where … the ENIAC is equipped with 18,000 vacuum tubes and weighs 30 tons, computers in the future may have only 1000 vacuum tubes and weigh only 1.5 tons – Popular Mechanics, 1949 IS 257 – Fall 2005 2005.11.21 - SLIDE 27 • There is no reason anyone would want a computer in their home. – Ken Olson, president and chair of Digital Equipment Corp., 1977. IS 257 – Fall 2005 2005.11.21 - SLIDE 28 • 640K ought to be enough for anybody. – Attributed to Bill Gates, 1981 IS 257 – Fall 2005 2005.11.21 - SLIDE 29 • By the turn of this century, we will live in a paperless society. – Roger Smith, Chair of GM, 1986 IS 257 – Fall 2005 2005.11.21 - SLIDE 30 • I predict the internet… will go spectacularly supernova and in 1996 catastrophically collapse. – Bob Metcalfe (3-Com founder and inventor of ethernet), 1995 IS 257 – Fall 2005 2005.11.21 - SLIDE 31 Lecture Outline • Review – Object-Oriented Database Development • Future of Database Systems • Predicting the future… • Quotes from Leon Kappelman “The future is ours” CACM, March 2001 • Accomplishments of database research over the past 30 years • Next-Generation Databases and the Future IS 257 – Fall 2005 2005.11.21 - SLIDE 32 Database Research • Database research community less than 40 years old • Has been concerned with business type applications that have the following demands: – Efficiency in access and modification of very large amounts of data – Resilience in surviving hardware and software errors without losing data – Access control to support simultaneous access by multiple users and ensure consistency – Persistence of the data over long time periods regardless of the programs that access the data • Research has centered on methods for designing systems with efficiency, resilience, access control, and persistence and on the languages and conceptual tools to help users to access, manipulate and design databases. IS 257 – Fall 2005 2005.11.21 - SLIDE 33 Accomplishments of DBMS Research • DBMS are now used in almost every computing environment to create, organize and maintain large collections of information, and this is largely due to the results of the DBMS research community’s efforts, in particular: – Relational DBMS – Transaction management – Distributed DBMS IS 257 – Fall 2005 2005.11.21 - SLIDE 34 Relational DBMS • The relational data model proposed by E.F. Codd in papers (1970-1972) was a breakthrough for simplicity in the conceptual model of DBMS. • However, it took much research to actually turn RDBMS into realities. IS 257 – Fall 2005 2005.11.21 - SLIDE 35 Relational DBMS • During the 1970’s database researchers: – Invented high-level relational query languages to ease the use of the DBMS for end users and applications programmers. – Developed Theory and algorithms needed to optimize queries into execution plans as efficient and sophisticated as a programmer might have custom designed for an earlier DBMS IS 257 – Fall 2005 2005.11.21 - SLIDE 36 Relational DBMS – Developed Normalization theory to help with database design by eliminating redundancy – Developed clustering algorithms to improve retrieval efficiency. – Developed buffer management algorithms to exploit knowledge of access patterns – Constructed indexing methods for fast access to single records or sets of records by values – Implemented prototype RDBMS that formed the core of many current commercial RDBMS IS 257 – Fall 2005 2005.11.21 - SLIDE 37 Relational DBMS • The result of this DBMS research was the development of commercial RDBMS in the 1980’s • When Codd first proposed RDBMS it was considered theoretically elegant, but it was assumed only toy RDBMS could ever be implemented due to the problems and complexities involved. Research changed that. IS 257 – Fall 2005 2005.11.21 - SLIDE 38 Transaction Management • Research on transaction management has dealt with the basic problems of maintaining consistency in multi-user high transaction database systems IS 257 – Fall 2005 2005.11.21 - SLIDE 39 No Transactions : Lost updates • • • • • John Read account balance (balance = $1000) Transfer $100 to Mel Debits $100 SYSTEM CRASH Read account balance (balance = $900) IS 257 – Fall 2005 Mel • Read account balance (balance = $1000) • SYSTEM CRASH • Read account balance (balance = $1000) ERROR! 2005.11.21 - SLIDE 40 No Concurrency Control: Lost updates John • Read account balance (balance = $1000) • Read account balance (balance = $1000) • Withdraw $200 (balance = $800) • Withdraw $300 (balance = $700) • Write account balance (balance = $800) • Write account balance (balance = $700) Marsha ERROR! IS 257 – Fall 2005 2005.11.21 - SLIDE 41 Transaction Management • To guarantee that a transaction transforms the database from one consistent state to another requires: – The concurrent execution of transactions must be such that they appear to execute in isolation. – System failures must not result in inconsistent database states. Recovery is the technique used to provide this. IS 257 – Fall 2005 2005.11.21 - SLIDE 42 Distributed Databases • The ability to have a single “logical database” reside in two or more locations on different computers, yet to keep querying, updates and transactions all working as if it were a single database on a single machine • How do you manage such a system? IS 257 – Fall 2005 2005.11.21 - SLIDE 43 Lecture Outline • Review – Object-Oriented Database Development • Future of Database Systems • Predicting the future… • Quotes from Leon Kappelman “The future is ours” CACM, March 2001 • Accomplishments of database research over the past 30 years • “Next-Generation Databases” and the Future IS 257 – Fall 2005 2005.11.21 - SLIDE 44 Next Generation Database Systems • Where are we going from here? – Hardware is getting faster and cheaper – DBMS technology continues to improve and change • OODBMS • ORDBMS – Bigger challenges for DBMS technology • Medicine, design, manufacturing, digital libraries, sciences, environment, planning, etc... IS 257 – Fall 2005 2005.11.21 - SLIDE 45 Examples • NASA EOSDIS – Estimated 1016 Bytes (Exabyte) • Computer-Aided design • The Human Genome • Department Store tracking – Mining non-transactional data (e.g. Scientific data, text data?) • Insurance Company – Multimedia DBMS support IS 257 – Fall 2005 2005.11.21 - SLIDE 46 New Features • • • • • • New Data types Rule Processing New concepts and data models Problems of Scale Parallelism/Grid-based DB Tertiary Storage vs Very Large-Scale Disk Storage • Heterogeneous Databases • Memory Only DBMS IS 257 – Fall 2005 2005.11.21 - SLIDE 47 Coming to a Database Near You… • • • • • • • • Browsibility User-defined access methods Security Steering Long processes Federated Databases IR capabilities XML The Semantic Web(?) IS 257 – Fall 2005 2005.11.21 - SLIDE 48 Some things to consider • Bandwidth will keep increasing and getting cheaper (and go wireless) • Processing power will keep increasing – Moore’s law: Number of circuits on the most advanced semiconductors doubling every 18 months • Memory and Storage will keep getting cheaper (and probably smaller) – “Storage law”: Worldwide digital data storage capacity has doubled every 9 months for the past decade • Put it all together and what do you have? – “The ideal database machine would have a single infinitely fast processor with infinite memory with infinite bandwidth – and it would be infinitely cheap (free)” : David DeWitt and Jim Gray, 1992 IS 257 – Fall 2005 2005.11.21 - SLIDE 49 IS 257 – Fall 2005 2005.11.21 - SLIDE 50