Database pptx. 1

Data

Raw facts that have not yet been processed to reveal meaning.

Information

The result of processing raw data to reveal its meaning; requires context.

Knowledge

Familiarity, awareness, and understanding of information.

Data Management

The discipline focused on the proper generation, storage, and retrieval of data.

Why is accurate, relevant, and timely information important?

It is the key to good decision making.

Database

A shared, integrated computer structure that stores end-user data and metadata.

End-user data

Raw facts of interest to the end user.

Metadata

Data about data; describes data characteristics and relationships between data.

DBMS (Database Management System)

A collection of programs that manages database structure and controls access to data.

Main purpose of a database

To store and manage data so that users can retrieve useful information from it.

File cabinet analogy

A database is like an electronic file cabinet: organized drawers and folders containing related information.

Hierarchical database

A type of database that organizes data in a hierarchical structure.

Network database

A type of database that organizes data using network relationships.

Relational database

A database perceived by users as a collection of tables.

Object-oriented database

A type of database that organizes data around objects.

Table

A logical structure in a relational database.

Cell

The intersection of a row and column.

Field

Another name for a column or attribute.

Attribute

Another name for a field or column.

Record

Another name for a row or tuple.

Tuple

Another name for a record or row.

SQL

Structured Query Language; the de facto query language and data access standard supported by most DBMS vendors.

Query

An instruction/question used to retrieve information from a database.

Why do we store data in a database?

To be able to retrieve data and information from it.

ERD

Entity Relationship Diagram; a tool used for database design.

Why is good database design important?

It facilitates data management and generates accurate and valuable information.

Database design

The activities focused on designing the database structure used to store and manage end-user data.

Decomposition

The process of properly breaking integrated data into its constituent parts.

Poor database design

Can cause difficult-to-trace errors that may lead to poor decision making.

Single-user database

A database that supports one user at a time.

Desktop database

A single-user database located on a personal computer.

Multiuser database

A database that supports multiple users at the same time.

Workgroup database

A database that supports a small number of users or a specific department.

Enterprise database

A database that supports many users across many departments.

Centralized database

A database in which data is located at a single site.

Distributed database

A database in which data is distributed across different sites.

Cloud database

A database created and maintained using cloud data services.

General-purpose database

A database containing a wide variety of data used in multiple disciplines.

Discipline-specific database

A database containing data focused on a specific subject area.

Operational database

A database designed to support a company's day-to-day operations.

Analytical database

A database that stores historical data and business metrics used for tactical or strategic decision making.

Data warehouse

A component of an analytical database that stores data in a format optimized for decision support.

OLAP

Online Analytical Processing; tools for retrieving, processing, and modeling data from a data warehouse.

Business intelligence

A comprehensive approach to capturing and processing business data to generate information that supports decision making.

Unstructured data

Data that exists in its original, raw state.

Structured data

Data that has been formatted to facilitate storage and use.

Semistructured data

Data that has already been processed to some extent.

XML

Extensible Markup Language; a language used to represent data elements in textual format.

XML database

A database that supports the storage and management of unstructured XML data.

NoSQL

Not Only SQL; a generation of DBMS that is not based on the traditional relational database model.

Why are NoSQL databases designed for modern business requirements?

They are designed to handle large volume, variety of data types and structures, and high velocity of data operations.

Manual file system

A system using physical file folders and filing cabinets to manage data.

Computerized file system

A computer-based system created to track data and produce required reports.

Spreadsheet misuse

Using a spreadsheet as a substitute for a database.

Field

A character or group of characters with a specific meaning used to define and store data.

Record

A logically connected set of one or more fields describing a person, place, or thing.

File

A collection of related records.

File system problems

Lengthy development times, difficulty getting quick answers, complex administration, lack of security, limited data sharing, and extensive programming.

Structural dependence

When access to a file is dependent on its own structure.

Structural independence

When the file structure can change without affecting the application's ability to access the data.

Data dependence

When data access programs must change when data storage characteristics change.

Data independence

When data storage characteristics can change without affecting a program's ability to access the data.

Logical data format

How humans view the data.

Physical data format

How the computer must work with the data.

Why is data dependence a problem?

It makes the file system cumbersome for programmers and database managers.

Data redundancy

When the same data is stored unnecessarily in different places.

Islands of information

Scattered data locations caused by data being stored in different places.

Problems caused by uncontrolled data redundancy

Poor data security, data inconsistency, data-entry errors, and data integrity problems.

Data anomaly

Occurs when not all required changes to redundant data are made successfully.

Update anomaly

One of the three types of data anomalies caused by redundant data.

Insertion anomaly

One of the three types of data anomalies caused by redundant data.

Deletion anomaly

One of the three types of data anomalies caused by redundant data.

Database system

A collection of logically related data stored in a single logical data repository, although data may be physically distributed.

How does a DBMS improve file-system problems?

It eliminates most data inconsistency, data anomaly, data dependence, and structural dependence problems.

Five components of a database system

Hardware, software, people, procedures, and data.

Hardware

Physical equipment used in the database system.

Software

Programs used to manage and operate the database system.

People

The users and professionals involved with the database system.

Procedures

Rules and processes governing the database system.

Data

The information stored and managed by the database system.

Data dictionary management

The DBMS stores definitions of data elements and their relationships

Data storage management

The DBMS creates and manages structures required for data storage.

Performance tuning

Ensures efficient database performance.

Data transformation and presentation

The DBMS transforms entered data to conform to required structures and formats it to meet users' logical expectations.

Security management

The DBMS enforces user security and data privacy.

Multiuser access control

Allows multiple users to access the database concurrently without compromising its integrity.

Backup and recovery management

Provides backup and recovery to ensure data safety and integrity.

Recovery management

Deals with recovering the database after a failure.

Data integrity management

Enforces integrity rules, minimizes redundancy, and maximizes data consistency.

Database access language

A language that allows users to specify what must be done without specifying how it must be done.

Database communication interfaces

Interfaces through which a DBMS accepts end-user requests.

DBMS disadvantage: Increased costs

Database systems can require greater financial resources.

DBMS disadvantage: Management complexity

Database systems can be complex to manage.

DBMS disadvantage: Maintaining currency

The database system must be kept current.

DBMS disadvantage: Vendor dependence

Organizations may become dependent on a database-system vendor.

DBMS disadvantage: Frequent upgrades/replacement cycles

Database systems may require frequent upgrades or replacement.

Database Developer

Creates and maintains database-based applications.

Database Designer

Designs and maintains databases.

Database Administrator

Manages and maintains DBMSs and databases.

Database Analyst

Develops databases for decision-support reporting.