McGraw-Hill/Irwin Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 14 Data and Database Administration

14-2 Outline  Organizational context  Tools of database administration  Processes for database specialists  Overview of processing environments

14-3 Database Support for Decision Making

14-4 Decision Making Examples

14-5 Information Life Cycle

14-6 Knowledge Management

14-7 Database Specialists  Data administrator  Middle or upper management  Broad view of information resources  Database administrator (DBA)  Support role  Emphasis on individual databases and DBMSs

14-8 Responsibilities of Specialists  Data administrator  Develops enterprise data model  Establishes inter database standards  Negotiates contractual terms  Database administrator  Performs database development tasks  Consults on application development  Evaluates DBMS capabilities and features

14-9 Database Administration Tools  Security  Integrity  Management of stored procedures and triggers  Data dictionary access

14-10 Database Access Control

14-11 Discretionary Access Control  Assign access rights or privileges to users  Specify ability to read, write, and delete specified parts of a database  Use views for fine level of control  Use groups to reduce the number of authorization rules

14-12 SQL Statements for Security I CREATE ROLE ISFaculty CREATE ROLE ISAdministrator WITH ADMIN CURRENT_ROLE CREATE ROLE ISAdvisor

14-13 SQL Statements for Security II GRANT SELECT ON ISStudentGPA TO ISFaculty, ISAdvisor, ISAdministrator GRANT UPDATE ON ISStudentGPA.StdGPA TO ISAdministrator REVOKE SELECT ON ISStudentGPA FROM ISFaculty RESTRICT GRANT ISAdministrator TO Smith WITH GRANT OPTION;

14-14 Common SQL Privileges

14-15 Oracle Security Statements  CREATE USER statement  Predefined roles  CONNECT  RESOURCE  DBA  System versus object privileges

14-16 Access Security Tools

14-17 Mandatory Access Control  Less flexible security approach for highly sensitive and static databases  Assign classification levels to database objects  Assign clearance levels to users  Access granted if a user's clearance level provides access to the classification level of a database object

14-18 Encryption  Encoding data to obscure its meaning  Plaintext  Ciphertext  Encryption key

14-19 SQL Domains  Limited ability to define new domains  CREATE DOMAIN statement CREATE DOMAIN StudentClass AS CHAR(2) CHECK(VALUE IN ('FR','SO','JR','SR') )  Distinct type CREATE DISTINCT TYPE USD AS DECIMAL(10,2);

14-20 SQL Assertions  Supports complex constraints  Constraint specified through a SELECT statement  Enforcement can be inefficient  Stored procedures and form events are alternatives

14-21 Assertion Example CREATE ASSERTION FullTimeEnrollment CHECK (NOT EXISTS ( SELECT Enrollment.RegNo FROM Registration, Offering, Enrollment, Course WHERE Offering.OfferNo =Enrollment.OfferNo AND Offering.CourseNo = Course.CourseNo AND Offering.RegNo = Registration.RegNo AND RegStatus = 'F' GROUP BY Enrollment.RegNo HAVING SUM(CrsUnits) >= 9 ) )

14-22 CHECK Constraints  Use when a constraint involves columns of the same table  Part of CREATE TABLE statement  Easy to write  Efficient to enforce

14-23 CHECK Constraints Example CREATE TABLE Student (… CONSTRAINT ValidGPA CHECK ( StdGPA BETWEEN 0 AND 4 ), CONSTRAINT MajorDeclared CHECK ( StdClass IN ('FR','SO') OR StdMajor IS NOT NULL ) )

14-24 Coding Practice Concerns  Documentation  Parameter usage  Content of triggers and stored procedures

14-25 Management of Dependencies  Referenced tables, views, and procedures  Access plans for SQL statements  DBMS support incomplete  Obsolete statistics  Remotely stored procedures  No automatic recompilation after deletion

14-26 Managing Trigger Complexity  Coding guidelines to minimize interaction  Trigger analysis tools  Additional testing for interacting triggers

14-27 Metadata  Define the source, use, value, and meaning of data  Stored in a data dictionary  DBMS data dictionary to track objects managed by the DBMS  Information resource dictionary to track objects relating to information systems development

14-28 Catalog Tables  Most DBMSs provide a large collection  Definition Schema and Information Schema in SQL:2003  Modify using data definition and control statements  Use SELECT statement to retrieve from catalog tables  Integrity of catalog tables is crucial

14-29 Sample Oracle Catalog Tables

14-30 Information Resource Dictionary

14-31 Processes for Database Specialists  Data planning  DBMS selection and evaluation

14-32 Goals of Data Planning  Evaluate current information systems with respect to the goals and objectives of the organization  Determine the scope and the timing of developing new information systems and utilizing of new information technology  Identify opportunities to apply information technology for competitive advantage

14-33 Planning Models

14-34 Level of Detail in Models

14-35 DBMS Selection  Detailed process  Requires knowledge of organization goals and DBMS features  Systematic approach is important  High switching cost if wrong choice

14-36 Selection Process Phases

14-37 Analytic Hierarchy Process  Multi-criteria decision making tool  Supports systematic assignment of weights and scores to candidate DBMSs  Uses pairwise comparisons

14-38 Rating Values for Comparisons Ranking Value of A ij Meaning 1Requirements i and j are equally important. 3Requirement i is slightly more important than requirement j. 5Requirement i is significantly more important than requirement j. 7Requirement i is very significantly more important than requirement j. 9Requirement i is absolutely more important than requirement j.

14-39 Analytic Hierarchy Process Details  Assign importance weights to pairwise combinations of requirement groups and requirement categories  Combine and normalize importance weights  Score candidate DBMSs for each requirement  Combine and normalize scores  Combine importance weights and DBMS scores

14-40 Final Selection Factors  Benchmarks and trial usage  Contractual terms  Vendor expectations

14-41 Benchmarking  Workload to evaluate the performance of a system or product  A good benchmark should be relevant, portable, scalable, and understandable.  Standard, domain-specific benchmarks by TPC

14-42 TCP Benchmarks  Reasonable estimates about a DBMS in a specific hardware/software environment  Total system performance and cost measures  Audits to ensure unbiased results

14-43 Current TCP Benchmarks  TPC-C: order entry benchmark  TPC-App: business to business transactions  TPC-H: decision support ad hoc queries  TPC-W: Ecommerce benchmark

14-44 Managing Database Environments  Transaction processing  Data warehouse processing  Distributed processing  Object data management

14-45 Responsibilities of Database Specialists  Application development  Database infrastructure and architectures  Performance monitoring  Enterprise data model development  Contingency planning

14-46 Summary  Two roles for managing information resources  Tools for security, integrity, rule processing, stored procedures, and data dictionary manipulation  Processes for data planning and DBMS selection  Context for studying other Part 7 chapters