ist 318 database administration lecture 1 what is dba?
TRANSCRIPT
IST 318 Database Administration
Lecture 1
What Is DBA?
Topics
DBMS and DB ApplicationsDatabase, Data, and System AdministrationDBA TasksTypes of DBAsTest and Production Environments
DB Applications
Data is the lifeblood of computerized applications In many ways, business today is data
Using DBMS is the efficient way for data persistence and manipulation
DBA is at the center of the development lifecycle
Database vs. DBMS
DatabaseAn organized store
of data Data can be
accessed by names
DBMSSoftware that
enable users or programmers to share and manage data
Enterprise IT Infrastructure – a big picture
Application Development Lifecycle
Data Administration
Concentrate on the business aspects Business lexicon logical data modelRequirements gathering, analysis, and design
Typical tasks include Identifying and cataloging business dataProducing conceptual and logical data modelsCreating enterprise data modelSetting data policies and standards
Concerns more about metadata
Metadata
Metadata is often described as data of dataDefinitionBusiness nameAbbreviationType and length/accuracyDomain, or range of valid values
Data Models – three levels
Conceptual modelOutlines data requirements at a very high levelDescribes data mostly in business context
Logical modelProvides in-depth details of data types, lengths,
relationships, and cardinality
Physical modelDefines the way data is organized in physical medium
DBA vs. DA
DBAs have to take care the first two levels if no DA roles are implemented in an organization
System Administration
SAs are more concerned about the installation and setup of DBMS
Typical SA tasks includeUnderlying OS systemsDBMS Installation, modification, and supportSystem configurations enabling DBMS to work with
other software systems
DBA Tasks
Ensuring data and databases are useful, usable, available, and correct
Typical DBA tasks includeDB design and implementationPerformance monitoring and tuningAvailabilityDB security and authorizationBackup and recoveryData integrityDBMS release migration
DB Design & Implementation
Understand and adhere to sound relational design principlesRelational theories and ER diagramsDBMS specifics
Understanding conceptual/logical models and being able to transform to physical DB implementationPoor design can result in poor performance
Performance Monitoring & Tuning
Performance = the rate at which the DBMS supplies info to its users
Influenced by five factorsWorkloadThroughputResourcesOptimizationContention
Availability
Multifaceted processKeep the DBMS up and runningMinimize the downtime required for admin tasks
Technologies and up-front planning can help
DB Security & Authorization
Ensure data is available only to authorized users by granting privileges to different (groups of) users
Actions need to be controlledCreating/altering DB objects and/or their structuresReading/modifying data from tablesStarting/stopping DB and/or associated objectsRunning stored procedures or DB utilities
Backup & Recovery
Be prepared to recover DB in the event of Improper shutdown of DB applications, due to
Software errorHuman errorHardware failure
Types of recoveryRecover to currentPoint-in-time recoveryTransaction recovery
Data Integrity
Store the correct data in the correct wayPhysical integrity
domains and data types
Semantic integrityquality data with no redundancy
Internal integrity internal structures and code
Desired Skill Set
SQL + PL/SQLSystem specific operations and practicesData modeling methodologies and toolsNetworking (client/server)O/SProgramming (conventional and web-oriented)Transactional/messaging systems
Types of DBAs
System DBADB architectDB analystData modelerApplication DBATask-oriented DBAData warehouse administrator
Test & Production
At least two separate environments must be created for quality DB implementationTesting (aka development) QA (aka staging)Production
DifferencesThey should share the same configurationThey don’t need to be identical
Testing DB may have only a subset of data
Multiple DB Environments