Data dictionary in dbms ppt

Database 9

1) Read chapter 15, IGU Online library and reputable resources and Describe the DBA's functions and responsibilities. (Chapter 15 attached).

2) Data and information is secure if the pyramid of security CIA (Confidentiality, Integrity , Availability) are satisfied. Discuss what each term means and provide an example to support your discussion.

Database Administration

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Objectives

Discuss the need for database administration
Explain the DBA’s responsibilities in formulating and enforcing database policies for access privileges, security, disaster planning, and archiving
Discuss the DBA’s administrative responsibilities for DBMS evaluation and selection, DBMS maintenance, data dictionary management, and training
Discuss the DBA’s technical responsibilities for database design, testing, and performance tuning
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Introduction

FIGURE 8-1: DBA responsibilities

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Database Policy Formulation and Enforcement

DBA
Formulates database policies
Communicates policies to users
Enforces policies
Policies
Access privileges
Security
Disaster planning
Archiving
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Access Privileges

DBA
Determines access privileges for all users
Enters appropriate authorization rules in DBMS
SQL GRANT statement
Access privilege policy
Documented by DBA
Approved by top-level management
Communicated by DBA to all users
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Access Privileges (continued)

FIGURE 8-2: Permitted and denied access privileges for Sam

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Access Privileges (continued)

FIGURE 8-4: Permitted and denied access privileges for Valerie

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Security

Prevention of unauthorized access, intentional or accidental, to database
DBA
Creates security policies and procedures
Obtains management approval of policies and procedures
Distributes policies and procedures to authorized users
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Security (continued)

DBMS’s security features
Encryption
Authentication
Authorizations
Views
Additional security programs may be created or purchased
Monitoring of database usage to detect security violations
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Security (continued)

FIGURE 8-5: Attempted security violation by Brady, who’s not an authorized user

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Security (continued)

FIGURE 8-6: Attempted security violation by Paige, who’s authorized to access some customer data but is not authorized to access customer balances

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Disaster Planning

Damage from physical incidents
Software/hardware/electrical
Natural disasters
Disaster recovery plan: ongoing and emergency actions and procedures to ensure data availability if a disaster occurs
Hard drive failures
Redundant array of inexpensive/independent drives (RAID): database updates replicated to multiple hard drives
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Disaster Planning (continued)

Electrical power loss
Uninterruptible power supply (UPS): power source and power generator
Duplicate backup systems
Hot site: completely equipped with duplicate hardware, software, and data
Can switch to hot site in minutes or hours
Warm site: duplicate hardware and software but not data
Takes longer to start processing
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Archiving

Governmental laws and regulations, for example:
Sarbannes-Oxley Act
Patriot Act
HIPAA
Auditing and financial requirements
Data archive or archive: place where record of certain corporate data is kept
Stored on mass storage devices
Copies of archives and database backups must be stored off-site
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Archiving (continued)

FIGURE 8-7: Movement of order 21617 from the database to the archive

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Other Database Administration Functions

DBMS evaluation and selection
DBMS maintenance
Data dictionary management
Training
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DBMS Evaluation and Selection

Data definition
Data restructuring
Nonprocedural languages
Procedural languages
Data dictionary
Concurrent update
Shared lock
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DBMS Evaluation and Selection (continued)

Backup and recovery
Security
Integrity
Replication and distributed databases
Limitations
Local area network (LAN)
Documentation and training
Context-sensitive help
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DBMS Evaluation and Selection (continued)

Vendor support
Performance
Portability
Intranet
Cost
Future plans
Other considerations
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DBMS Maintenance

Installation of DBMS
Configuration changes
Upgrades for new releases
Problem resolution
Special one-time processing needs
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Data Dictionary Management

Data dictionary is like database catalog, but with wider range of information
Establishes naming conventions for tables, fields, indexes, etc.
Creates data definitions for tables
Creates data integrity rules and user views
Updates data dictionary
Creates and distributes reports from data dictionary
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Training

Training in using DBMS and accessing database
Training of technical staff responsible for developing and maintaining database applications
If training is provided by vendor of DBMS, DBA handles scheduling of training
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Technical Functions

Database design
Testing
Performance tuning
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Database Design

Establishes sound methodology for database design
Does physical-level design
Creates documentation standards
Reviews changes to requirements and manages modifications to database
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Testing

Production system or live system: hardware, software, and database for users
DBA grants access to production system only to authorized users, except for:
Troubleshooting a problem
Addition of new or modified programs
Test system or sandbox: used by programmers to develop new programs and modify existing programs
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Testing (continued)

FIGURE 8-9: DBA controls the interaction between the test and production systems

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Performance Tuning

DBA attempts to get best performance within funding constraints
Creating and deleting indexes
Splitting tables
Changing table design
Denormalizing converts a table in third normal form to a table not in third normal form
Improved performance
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Performance Tuning (continued)

FIGURE 8-10: Customer table for Premiere Products

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Performance Tuning (continued)

FIGURE 8-11: Result of splitting the Customer table into two tables

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Performance Tuning (continued)

FIGURE 8-11: Result of splitting the Customer table into two tables (continued)

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Performance Tuning (continued)

FIGURE 8-12: Including part descriptions in the OrderLine table, which creates a first normal form table

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Summary

Database administrator (DBA) is responsible for supervising the database and use of the DBMS
DBA formulates and enforces policies about which users can access database, portions they may access, and the manner in which they can access it
DBA formulates and enforces policies about security by using DBMS’s security features, special security programs, and monitoring database usage
DBA creates and implements backup and recovery procedures as part of a disaster recovery plan
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Summary (continued)

DBA formulates and enforces policies that govern management of an archive for data
DBA leads evaluation and selection of new DBMS
DBA installs and maintains DBMS
DBA maintains data dictionary, establishes naming conventions for its content, and provides information from it to others
DBA provides database and DBMS training and coordinates and schedules training by outside vendors
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Summary (continued)

DBA verifies all information-level database designs, completes all physical-level database designs, and creates documentation standards; also evaluates changes in requirements
DBA controls production system, which is accessible only to authorized users; other than under exceptional situations, programmers access a separate test system
DBA tunes database design to improve performance; includes creating and deleting indexes, splitting tables, and denormalizing tables