Introduction to DB2 9 for z/OS

This chapter addresses the job responsibilities of the DB2 system administrator, describes what to expect on the IBM DB2 9 System Administrator for z/OS Exam (Test 000-737), and reviews the basic prerequisites assumed for the reader of this book.

Purpose of the Book

As the certification study guide for Test 737, this book guides you through the responsibilities, tasks, and methods used by a DB2 9 for z/OS system administrator. It covers all the objectives of the exam and provides sample exam questions and answers to test your knowledge.

The book provides a broad understanding of the responsibilities of a DB2 for z/OS system administrator, gives examples of day-to-day work requirements, describes techniques to assist you in your work, and provide details about how to develop your skill sets.

Test 737: DB2 9 System Administrator for z/OS

The system administrator exam certifies that the candidate has the skills, knowledge, and abilities to describe the architecture and administer the processes required to plan, install, manage, and tune secure DB2 for z/OS environments. To obtain this certification, you must pass two tests:

• Test 730: DB2 9 Family Fundamentals

• Test 737: DB2 9 System Administrator for z/OS

Test 737 is 90 minutes in duration and consists of 60 questions. The passing score is 62 percent. The exam consists of six sections, each of which includes questions and some scenarios for you to evaluate:

• Section 1: Installation and Migration (15 percent of the test) — Tests your knowledge of the installation and migration planning process, how to execute an installation/migration plan, and how to evaluate appropriate subsystem parameter (DSNZPARM) configuration settings (Chapter 3)

• Section 2: Security and Auditing (7 percent) — Assesses your understanding of how to protect DB2 resources, auditing techniques, and role-based security (Chapter 4)

• Section 3: System Operation and Maintenance (21.5 percent) — Deals with the management of DB2 components, commands, monitoring, and threads (Chapter 7)

• Section 4: Backup and Recovery (20 percent) — Tests your knowledge of the procedures for system-level backup, recovery from system failures, and disaster recovery processes (Chapter 5)

• Section 5: Performance and Tuning (21.5 percent) — Presents scenarios and asks you to analyze the performance; tests your knowledge of buffer pools, DSNZPARMs, statistics, traces and tools, efficient use of memory, and DB2 workload manager settings (Chapter 6)

• Section 6: Troubleshooting (15 percent) — Tests your problem-solving abilities, including your knowledge of operator commands and traces, how to identify contention problems, diagnostics in dealing with utilities, and resolving and identifying data sharing problems (Chapter 7)

Certification Web Site

The IBM Professional Certification Program Web site, http://www.ibm.com/certify, provides information that can help you prepare for the exam, including a sample test, a list of training resources to help you prepare for the exam, and information about testing centers worldwide. Take the time to visit this site and become familiar with the information it offers.

The sample assessment test is a good place to start. You can practice taking the exam and see how well you score on each section to evaluate your strengths and weaknesses. Remember, though, that passing the sample test does not result in credentials. For instructions about how to access the Web-based assessment test delivery tool, including registration and payment procedures, see the information page for Test 737.

DB2 System Administration Requirements

To work as a DB2 9 for z/OS system administrator, you need a strong background in DB2 for z/OS. For example, if you are currently a database administrator with a couple years of experience, or if you have several years as a DB2 advanced programming lead under your belt, you have the baseline to start working on your system administration skill set and certification.

Your understanding and background should include familiarity with the DB2 and System z architectures.

Knowledge of DB2

Your DB2 experience should include the following:

• DB2 catalog tables, DB2 directory, bootstrap data sets (BSDSs)

• DB2 active and archive logging

• DB2 virtual buffer pools (VBPs)

• SQL query writing, EXPLAIN, and troubleshooting

• Data Definition Language (DDL) and physical structures in DB2

• DB2 IBM administration tools and the Optimization Service Center (OSC)

• IBM or other vendor DB2 utilities (e.g., COPY, LOAD, RUNSTATS)

System z Architecture

Your z/OS skill set should include the following:

• How to write Job Control Language (JCL) to execute a job in z/OS

• How to use the Interactive System Productivity Facility (ISPF) and Program Development Facility (PDF) to display data set lists or define a data set

• How to use the System Display and Search Facility (SDSF) and/or the Interactive Output Facility (IOF) to find job execution information

• Familiarity with the System Modification Program/Extended (SMP/E) tool and its basic functions

• Knowledge of Workload Manager (WLM) and its basic functions

Familiarity with other software products, such as Customer Information Control System (CICS), WebSphere, and non-IBM vendor offerings is a plus. We will build on your DB2, z/OS, and product skills throughout this book.

To obtain more information about DB2 9 for z/OS, visit IBM's DB2 for z/OS Web site, http://www-01.ibm.com/software/data/db22/zos, where you will find downloads, product support, product documentation, and more.

DB2 for z/OS Overview

This chapter reviews the tasks, services, structure, architecture, and components of DB2 9 for z/OS that constitute required knowledge for a DB2 system administrator.

CSECTs and Subcomponents

Let's begin with a short overview of how the DB2 code is structured internally:

• In DB2, each object module contains a single control section (CSECT).

• A CSECT typically performs one function, and the object module and CSECT have the same name.

• Member DSNWMODS in library SDSNSAMP contains the readable data set associated with a CSECT for DB2.

• CSECT names and message identifiers begin with the letters "DSN" in DB2.

• The fourth character of a DB2 CSECT name identifies a subcomponent. For example, the...