Advanced Topics Chapter Seven DAVID M. KROENKE’S DATABASE CONCEPTS, 2 nd Edition

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-2 Chapter Objectives Understand the nature, need and importance of the following topics:  Web database processing  Database processing with XML  Distributed database processing  OLAP and data mining  Object-relational database management

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-3 Web Database Processing Client computers use browsers Web server communicates via Hypertext Transfer Protocol (HTTP) and scripting / programming languages to browsers and DBMS DBMS communicates with database

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-4 Web Database Processing Environment

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-5 N-Tier Architecture Tiers refers to the number of computers involved in the Web database application –The user’s workstation with its’ Web browser is the first tier –Two-tier architecture means that the Web server and the DBMS are on the same server –Three-tier architecture means that the Web server and the DBMS are on separate servers

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-6 Typical Web Server Setups Microsoft Windows Linux or Unix Web ServerInternet Information Server (IIS) Apache Scripting Languages (Interpreted ASP Pages with VBScript or JScript (PHP also works) PHP Object Oriented Languages (Complied) ASP.NET pages with VisualBasic.Net, C#.Net or others JSP pages with Java (Also see the Mono project)Mono

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-7 Typical Web DBMS Servers Microsoft Windows Linux or Unix Web ServerInternet Information Server (IIS) Apache DBMSsMicrosoft SQL Server Oracle MySQL API Interface Standard ODBCJDBC

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-8 API Interface Standards Every DBMS has a different application program interface (API) API interface standards are used to make it easier for programmers – they write to the interface standard instead of the DBMS API –OBDC – Open Database Connectivity –JDBC – Not an acronym for anything! (in particular, not Java Database Connectivity)

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-9 Sample HTML Code <META HTTP-EQUIV="Content-Type" CONTENT="text/html;charset=windows- 1252"> Artist

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-10 Sample ASP Code <% Dim objConn, objRecordSet, varSql If IsObject(Session("_conn")) Then ' if already have a connection, use it Set objConn = Session("_conn") Else Set objConn = Server.CreateObject("ADODB.connection") ' get connection objConn.open "ViewRidgeSS" ' open VRG database using operating system authentication objConn.IsolationLevel = adXactReadCommitted ' avoid dirty reads Set Session("_conn") = objConn End If

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-11 Sample ASP Code (continued) Set objRecordSet = Server.CreateObject("ADODB.Recordset") ' create the record set object varSql = "SELECT Name, Nationality FROM ARTIST" ' set up SQL command objRecordSet.Open varSql, objConn, adOpenStatic, adLockReadOnly ' static with no need to update %>

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-12 Database Procesing with XML Extensible Markup Language (XML) is a standard for defining the structure of documents and communicating the documents among computers It provides user definable tags that can be used in Web pages and other documents

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-13 Sample XML document Michelle Correlli 1824 East 7th Avenue Suite 700 Memphis TN

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-14 XML Schema Documents XML schema documents define allowable tags and their relationships

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-15 XML Document Validation An XML document can declare the name and location of the schema that defines its tags XML documents that conform to their XML schemas are schema-valid documents XML schema documents are XML documents, and can be validated against their designated schema The “Schema of all schemas” is at

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-16 Sample XML Schema

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-17 XML and Database Processing DBMS programs are incorporating means to read and create XML documents SQL Server example: SELECT * FROM ARTIST FOR XML AUTO, ELEMENTS;

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-18 XLM Web Services XML Webs Services allows application functionality on one Web server to be shared and incorporated into Web applications on other Web servers

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-19 Distributed Database Processing A database is distributed when it is: –Partitioned –Replicated –Both partitioned and replicated This is fairly straight forward for read- only replicas, but it can be very difficult for other installations

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-20 Type of Distributed Databases

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-21 OLAP and Data Mining OnLine Analytical Processing (OLAP) is a technique for dynamically examining database data –OLAP uses arithmetic functions (Sum, Average, etc) Data Mining is a mathematically sophisticated technique for analyzing database data –Data mining use mathematical and statistical techniques

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-22 OLAP OLAP uses a table called an OLAP cube The OLAP cube uses inputs called dimensions The OLAP cube calculates outputs called measures

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-23 Sample OLAP Cube

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-24 Data Mining Techniques Data Mining mathematical and statistical techniques include: –Cluster analysis –Regression analysis –Time-series analysis –Factor analysis –Nonparametric Monte Carlo analysis

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-25 Object-Relational Database Management Object-oriented programming (OOP) is based on objects, and OOP is now used as the basis of many computer programming languages –Java –VisualBasic.Net –C++ –C#

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-26 Objects Object classes have –Identifiers –Properties These are data items associated with the object –Methods These are programs that allow the object to perform tasks The only difference between entity classes and object classes is the methods.

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-27 Object Persistence Object persistence means that values of the object properties are storable and retrievable Object persistence can be achieved by various techniques –A main technique is database technology –Relational databases can be used, but require substantial programming

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-28 OODBMS Object-Oriented DBMSs (OODBMSs) have been developed –Never achieved commercial success It would be too expensive to transfer existing data from relational and other legacy databases Therefore, the OODBMSs were not cost justifiable

DAVID M. KROENKE’S DATABASE CONCEPTS, 2nd Edition © 2005 Pearson Prentice Hall 7-29 Object-Relational DBMSs Some relational DBMS vendors have added object-oriented features to their products –Oracle These products are known as object- relational DBMSs and support object- relational databases

Advanced Topics End of Presentation on Chapter Seven DAVID M. KROENKE’S DATABASE CONCEPTS, 2 nd Edition