database management systems cse 594
DESCRIPTION
Database Management Systems CSE 594. Introduction September 28, 2000. Staff. Instructor: Alon Halevy Sieg, Room 310, [email protected] Office hours: Thursdays 5pm, email. TAs: Maya Rodrig Office hours: Thursdays 5pm, or by appointment. Mailing list: cse594@cs - PowerPoint PPT PresentationTRANSCRIPT
Database Management Systems
CSE 594
IntroductionSeptember 28, 2000
StaffInstructor: Alon Halevy
Sieg, Room 310, [email protected] Office hours: Thursdays 5pm, email.
TAs: Maya Rodrig Office hours: Thursdays 5pm, or by
appointment.Mailing list: cse594@csWeb page:
http://www.cs.washington.edu/education/courses/594/00au/
Goals of the CoursePurpose:
Principles of building database applications Foundations of database management systems. Issues in building database systems. Have fun: databases are not just bunches of tuples. Not an introduction to the nitty gritty of any
specific commerical system.
Grading
Paper homeworks: 25% Very little regurgitation. Meant to be challenging (I.e., fun).
Two programming projects: 40% Work in pairs. Build a database application Build an XML query processor
Final Exam: 25% (currently scheduled for Dec. 14th).
Intangibles (e.g., participation): 10%
TextbookTwo volume collection, available as a
pair in the bookstore:A First Course on Database Systems:
Ullman & WidomDatabase System Implementation:
Garcia-Molina, Ullman and Widom.A few comments about the books.
Other Useful Texts Database Management Systems: Ramakrishnan and
Gehrke Foundations of Databases (Abiteboul, Hull & Vianu) Parallel and Distributed DBMS (Ozsu and Valduriez) Transaction Processing (Gray and Reuter) Database Systems (Silberschatz, Korth and
Sudarshan) Principles of Transaction Processing (Bernstein and
Newcomer) Readings in Database Systems (Stonebraker and
Hellerstein) Proceedings of SIGMOD, VLDB, PODS conferences.
Prerequisites
Real PrerequisitesOperating systemsData structures and
algorithmsDistributed systemsComplexity theoryMathematical LogicKnowledge
Representation
User interface design
Programming languages
Artificial Intelligence (Search)
Greek, Hebrew, French
Why use a DBMS?Suppose we are building a system to store the
information pertaining to the university. Several questions arise:how do we store the data? (file organization, etc.)how do we query the data? (write programs…)make sure that updates don’t mess things up?Provide different views on the data? (registrar versus
students)how do we deal with crashes?Way too complicated! Go buy a database system!
Why Use a DBMS?
• Large amounts of data (Giga’s, Tera’s) • Data is very structured• Persistent data• Valuable data• Performance requirements• Concurrent access to the data• Restricted access to data
All programs manipulate data, so why use a database?Many data manipulation tasks involve recurringoperations:
Functionality of a DBMSPersistent storage managementTransaction managementResiliency: recovery from crashes.Separation between logical and physical
views of the data. High level query and data manipulation
language. Efficient query processing
Interface with programming languages
Bird’s Eye View ofHow to build a database application
The different components of a database system.
Building an Application with a Database System
Requirements modeling (conceptual, pictures) Decide what entities should be part of the application and
how they should be linked.Schema design and implementation
Decide on a set of tables, attributes. Define the tables in the database system. Populate database (insert tuples).
Write application programs using the DBMS way easier now that the data management is taken care
of.
address name field
Professor
Advises
Takes
Teaches
CourseStudent
name category
quarter
name
ssn
Conceptual Modeling
Relational Terminology
Name Price Category Manufacturer
gizmo $19.99 gadgets GizmoWorks
Power gizmo $29.99 gadgets GizmoWorks
SingleTouch $149.99 photography Canon
MultiTouch $203.99 household Hitachituples
Attribute namesProduct (relation name)
Product(name: string, Price: real, category: enum, Manufacturer: string)
(Arity=4)
Schema Design and ImplementationTable Students
Note: Separation of the logical view from the physical view of the data.
Normalization (theory).
Student Course Quarter
Charles CS 444 Fall, 1997
Dan CS 142 Winter,1998
… … …
Querying a DatabaseFind all the students who have taken CSE444 in
Fall, 1997.S(tructured) Q(uery) L(anguage)
select E.name from Enroll E where E.course=CS444 and E.quarter=“Fall, 1997”
Query processor figures out how to answer the query efficiently.
An acquired taste…Other query languages exist (OO, OR, datalog)
Writing Application CodeUse ODBC/JDBC.Create a connection with a database.Embed SQL in application code.Specify transaction bordersMay need physical tuning of the
database.
Query optimizer
Execution engine
Index/record mgr.
Buffer manager
Storage manager
storage
User/Application
Queryupdate
Query executionplan
Record, indexrequests
Page commands
Read/writepages
Storage ManagementBecomes a hard problem because of the
interaction with the other levels of the DBMS: What are we storing? Efficient indexing, single and multi-
dimensional Exploit “semantic” knowledge
Issue: interaction with the operating system. Should we rely on the OS?
TP and RecoveryFor efficient use of resources, we want
concurrent access to data.Systems sometimes crash.A “real” database guarantees ACIDACID:
Atomicity: all or nothing of a transaction. Consistency: always leave the DB consistent. Isolation: every transaction runs as if it’s the only
one in the system. Durability: if committed, we really mean it.
Do we really want ACID?
ReviewsSh ip p in gO rd ersIn ven toryBooks
m ybooks .com M edia ted S chem a
W e s t
...
F e dE x
W A N
a lt.bo o ks .re v ie w s
In te rne tIn te rne t In te rne t
UP S
E a s t O rde rs C us to me rR e v ie w s
NY Time s
...
M o rga n-K a ufma n
P re ntice -Ha ll
Data Integration
Uniform query capability across autonomous, heterogeneous data sources on LAN, WAN, or Internet
XML: Semi-structured Data
Emerging format for data exchange on the web and between applications.
<db> <book> <title>Complete Guide to DB2</title> <author>Chamberlin</author> </book> <book> <title>Transaction Processing</title> <author>Bernstein</author> <author>Newcomer</author> </book> <publisher> <name>Morgan Kaufman</name> <state>CA</state> </publisher></db>
eXtensible Markup Language:
Database Industry
Relational databases are a great success of theoretical ideas.
Oracle has a market cap of over $200BOther players: IBM, MS, Sybase, InformixTrends:
warehousing and decision support data integration XML, XML, XML.
Course (Rough) OutlineThe basics: (quickly)
The relational model SQL Views, integrity constraints
XMLPhysical representation:
Index structures.
Course Outline (cont)Query execution: (Zack Ives)
Algorithms for joins, selections, projections.
Query OptimizationData Integrationsemi-structured dataTransaction processing and recovery
(Phil Bernstein)
ProjectsGoal: identify and solve a problem in database
systems.(almost) anything goes.Groups of 2-3Groups assembled end of week 2;Proposals, end of week 3.Touch base with me: every two weeks.Example projects on web site.Start Early.