Chapter 14 Data and Database Administration

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Outline Organizational context Tools of database administration Processes for database specialists Overview of processing environments

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Support for Decision Making

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Decision Making Examples

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Information Life Cycle

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Knowledge Management

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Specialists Data administrator –Middle or upper management –Broad view of information resources Database administrator (DBA) –Support role –Emphasis on individual databases and DBMSs

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Administration Tools Security Integrity Management of stored procedures and triggers Data dictionary access

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Access Control

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. SQL Statements for Security I CREATE ROLE ISFaculty CREATE ROLE ISAdministrator WITH ADMIN CURRENT_ROLE CREATE ROLE ISAdvisor

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Common SQL Privileges

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Oracle Security Statements CREATE USER statement Predefined roles –CONNECT –RESOURCE –DBA System versus object privileges

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Access Security Tools

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Encryption Encoding data to obscure its meaning Plaintext Ciphertext Encryption key

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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);

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. SQL Assertions Supports complex constraints Constraint specified through a SELECT statement Enforcement can be inefficient Stored procedures and form events are alternatives

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 ) )

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. CHECK Constraints Use when a constraint involves columns of the same table Part of CREATE TABLE statement Easy to write Efficient to enforce

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 ) )

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Coding Practice Concerns Documentation Parameter usage Content of triggers and stored procedures

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Managing Trigger Complexity Coding guidelines to minimize interaction Trigger analysis tools Additional testing for interacting triggers

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Catalog Tables Most DBMSs provide a large collection Definition Schema and Information Schema in SQL:1999 Modify using data definition and control statements Use SELECT statement to retrieve from catalog tables Integrity of catalog tables is crucial

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Sample Oracle Catalog Tables

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Information Resource Dictionary

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Processes for Database Specialists Data planning DBMS selection and evaluation

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Planning Models

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Level of Detail in Models

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. DBMS Selection Detailed process Requires knowledge of organization goals and DBMS features Systematic approach is important High switching cost if wrong choice

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Selection Process Phases

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Analytic Hierarchy Process Multi-criteria decision making tool Supports systematic assignment of weights and scores to candidate DBMSs Uses pairwise comparisons

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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.

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Final Selection Factors Benchmarks and trial usage Contractual terms Vendor expectations

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. TCP Benchmarks Reasonable estimates about a DBMS in a specific hardware/software environment Total system performance and cost measures Audits to ensure unbiased results

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Managing Database Environments Transaction processing Data warehouse processing Distributed processing Object data management

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Responsibilities of Database Specialists Application development Database infrastructure and architectures Performance monitoring Enterprise data model development Contingency planning

McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 4 chapters