Oracle Database Administration Session 1 CSCI E-256 Introduction The Role of the DBA

Introduction What is Database ? What is Database Administration ? What is an Oracle DBA ? What do they do ? How do they do it ?

The Database Most people view a database as the collection of data from a business An application presents this data to the users in a manageable way. The application can insert, delete or update the data. The database structures hold and manipulate this data

The Database The Data is stored in Relational Tables, defined by Columns Data is stored as Rows in a table These tables can then be related to each other, using relationships The database enforces these relationships

Types of Database Online Transaction Processing (OLTP) – Amazon.com Decision Support (DSS) – OLTP database used for reports Operational Data Store (ODS) – OLTP database plus summary data Data Warehouse – special set of structures, star schema

OLTP Online Transaction Processing Data dependency Model Many-to-many relationships Many-to-one relationships If we have more detailed data, it must be better Normalization

Operational Data Store (ODS) An ODS has been defined as Subject oriented Integrated Volatile Current valued Comprised of only corporate detailed data

Data Warehouse A Data Warehouse is a collection of integrated, subject-oriented databases designed to support the DSS (decision support) function, where each unit of data is relevant for some moment in time W. H. Inmon The data should be Well defined Consistent Non-volatile (read-only)

Data Warehouse Any information, from anywhere, of anytime, from internal and external data sources This includes operational, historical and legacy data It can also include data from Internet service providers and subscription databases It must include Metadata ( data about data)

Applications Most are Web based. SQL (sequel) is a language used to interface with various rdbms environments Embedded SQL (Java, C++, etc)

The Oracle DBA What is the Role of the DBA Newer Issues Planning, design and development Ongoing maintenance Data Administrator Security Newer Issues Uptime Backups with shorter windows Larger environments More visible

The Oracle DBA Roles The Systems or Operational DBA The Architect The Applications DBA The Data DBA The Internet DBA – Webmaster

The DBA Tasks Software Installation Software Additions Software Upgrades Database Creation Database Standards Performance Security

DBA Tasks Software Installation Software Additions Software Upgrades Setup the initial environment Software Additions Software Upgrades What are the current releases

DBA Tasks Log SR’s (Service Request) Applying Patches System Tuning System level Database level Application level

DBA Tasks Database Issues Move/Copy a database Development Issues Database Standards Security policies

DBA Tasks Education of others Reading, magazines… Third Party Software Monitoring Tools Automation

How DBAs spend their time Install 6% Create and Configure 12% Load Data 6% Manage Database System 55% Note: DBA time allocation statistics are based on the IOUG 2001 DBA Survey. Maintain Software 6%

The Past and the Present Environment Limited scalability, no resource sharing Must be configured for peak loads, when implemented Single points of failure Slow to adjust to the new needs of the business Islands of computation

Grid Computing Storage Grid Database Grid Application Server Grid Control

Grid Vision Computing as a utility Client-side: Simplicity A network of clients and service providers Cloud Computing Virtualization Nothing more virtual than a utility Massive potential Client-side: Simplicity Request computation or information and receive it Server-side: Sophistication Availability, reliability, security Capacity on demand, load balancing

The E-256 Course …. System level issues Installation of the RDBMS software Adding more software options Upgrading to a new level of the RDBMS and the issues related to this Applying patches to the RDBMS

The E-256 Course …. Create a database “instance” Database Security, create users, roles … Create database objects, tables, indexes, etc. Examine the storage parameters the database objects above Oracle utilities, export, import, etc Database Networking Issues

The E-256 Course …. How to manage the database using database “views” How to “backup” the database How to “recover” the database Performance management How to get help from Oracle Oracle Enterprise Manager

The Approach Where does the database fit in the big picture The technical architecture of an application Frameworks (examples) Management Performance Backup/Recovery Security

The Approach Knowledge Work Research Methods Scenario Thinking Project Management An Intentional Methodology

The Instance What is an Oracle database A database instance (server) is a set of memory structures and background processes, that access a set of database files The memory structure is the SGA (System Global Area)

The Physical World The computer system The operating system Memory Storage Processors Daemons printers Networks Files

The Logical World A Tablespace is a logical division of a database. Each tablespace is made up of one or more files, called datafiles. A datafile belongs to one tablespace A table is a logical structure, inside a tablespace

Oracle Flexible Architecture (OFA) /u01 - Oracle Base and Oracle Home /u01/app/oracle Oracle Base directory /u02 - The Application Home /u03 - General Usage /u04 - Oracle Datafiles

Oracle Flexible Architecture (OFA) /u05 thru /u09 /u04/oradata/<SID> Example: /u04/oradata/test SID is the database identifier

Oracle Directory Structure

Database Structures Three Types Internal to the Database Memory Based (SGA and Processes) External to the Database

Internal Database Structure Examples Table The only way to store data in a database Indexes It is a partial copy of a table, used to help speed up accessing the data in the table Views A method of looking at “some” of the data in a table or group of tables

Internal Database Structures Procedures Blocks of PL/SQL statements, called by applications They do not return a value to the calling program Functions Like a procedure, but can return a value to the calling program.

Internal Database Structures Packages These hold procedures and functions in logical groups A package can have PUBLIC and PRIVATE elements Public, would be procedures for a USERS usage Private may be called by other procedures in the package

Internal Database Structures Triggers Procedures that execute when a specific event occurs Used to augment referential integrity, enforce additional integrity Statement triggers Row triggers

Internal Database Structures Sequences Sequential lists of unique numbers Used as primary Keys Users Schemas Database Links Undo Segments (rollback segments)

Memory Structures System Global Area (SGA) Unix level processes Part of the System Memory Unix level processes

The System Information on a computer is stored in bytes Bytes are grouped into Blocks The Operating System usually has 512 bytes in a block 1K = 1024 bytes Oracle data is also stored in bytes Oracle data blocks are in 2k,4k,8k,16, or 32k bytes

The System Oracle data blocks are multiples of the Operating System blocks The computer memory uses the same block sizes as the disk storage Space allocation

Security Users and Roles Security Patching Advanced Security Option Sql*net encryption Application level security Sql injection

The Learning Environment Distance Option Blog Method TA session Online TA session Elluminate Website Books

Website Website at http://courses.fas.harvard.edu/ext/22750 www.elluminate.com

How do you know you got it Understand the Concepts Be able to create a maintainable database Walk-away with a framework approach Understand where that database fits within the technology stack The Future Security Auditing High Availability Semantic Web

Security Framework

Environment Boundaries

Strategic and Tactical

Overall Strategic and Tactical System Level Database Level