IM 101 Flashcards
evolved from computer file systems. Understanding file
system characteristics is important.
Databases
Used in almost all modern settings involving data management:
- Business
- Research
- Administration
The difference between data and information.
Data are raw facts. Information is processed data to reveal the meaning behind the facts.
a discipline that focuses on the proper generation, storage, and retrieval
of data.
Data Management
Data Hierarchy
Bit>Byte>Field>Record>File>Database
shared, integrated computer structure that stores a collection of end-user data and Metadata.
Database
raw facts of interest to end user
End-user data
data about data
* Provides description of data characteristics and relationships in data
* Complements and expands value of data
Metadata
Number of users
Single-user:
Desktop
Multi-user
Workgroup
Enterprise
Supports only one user at a time.
Single User
Single-user database running on a personal computer.
Desktop
Supports multiple users at the same time.
Multi-user
Multi-user database that supports a small group of users or a single
department.
Workgroup
Multi-user database that supports a large group of users or an entire
organization.
Enterprise
Database site location
Centralized
Distributed
Supports data located at a single site.
Centralized
Supports data distributed across several sites.
Distributed
Type of data
General Purpose
Discipline-Specific
Supports a company’s day-to-day
operations.
Transactional (production) database (OLTP)
Stores data used to generate information required
to make tactical or strategic decisions. Often used to store historical data structure is quite
different.
Data warehouse database (OLAP)
Each data item in a tree is called a node. Degree of a Node:
The degree of a node of a tree is the number of subtrees having this node as a root. In
other words, the degree is the number of descendants of a node. If the degree is zero, it
is called a terminal or leaf node of a tree.
Degree of data structure
Data whose elements are addressable for
effective analysis. It has been organized into a formatted repository that is typically a
database. It concerns all data which can be stored in database SQL in a table with rows
and columns.
Structured data
data is information that does not reside in a
relational database but that has some organizational properties that make it easier to
analyze.
Semi-structured data
data which is not organized in a
predefined manner or does not have a predefined data model, thus it is not a good fit
for a mainstream relational database.
Unstructured data
stores and organizes data and can be thought of as a type of index for all the data
contained in a storage device. These devices can include hard drives, optical drives and flash
drives.
File System
stored separately from the contents of the file, with many file systems storing the file
names in separate directory entries.
Metadata
supported by the Microsoft Windows OS. FAT is considered simple
and reliable, and it is modeled after legacy file systems. FAT was designed in 1977 for floppy
disks, but was later adapted for hard disks. While efficient and compatible with most current
OSes, FAT cannot match the performance and scalability of more modern file systems.
File Allocation Table(FAT)
a file system for the Linux OS, and it is a shared disk file system.
GFS offers direct access to shared block storage and can be used as a local file system.
Global file system (GFS)
developed for use with Mac operating systems. HFS can
also be referred to as Mac OS Standard, and it was succeeded by Mac OS Extended. Originally
introduced in 1985 for floppy and hard disks, HFS replaced the original Macintosh file system. It
can also be used on CD-ROMs.
Hierarchical file system (HFS)
the default
file system for Windows products from Windows NT 3.1 OS onward.
NT file system / New Technology File System (NTFS)
a vendor-neutral file system used on optical media and DVDs.
UDF replaces the ISO 9660 file system and is the official file system for DVD video and audio as
chosen by the DVD Forum.
Universal Disk Format (UDF)
creates and defines the restraints for a database.
Database management system (DBMS)
It requires that each transaction be “all or nothing“. If one part of the
transaction fails, the entire transaction fails, and the database state is left unchanged. On
the other hand, if one part of the transaction is successful, then it should be reflected in
the database.
Atomicity.
The consistency property ensures that any transaction will bring the
database from one valid state to another.
Consistency
It ensures that the concurrent execution of transactions result in a system state
that would be obtained if transactions were executed serially, one after the other.
Isolation
This means that once a transaction has been committed, it will remain so, even
in the event of power loss, crashes, or errors.
Durability
defines and regulates the collection, storage, management, and use of data.
Database System
It is refers to all the database system’s physical devices.
Hardware
It refers to the components that are needed to make the database function
fully.
Software
It manages all hardware components and makes it
possible for all other software to run on the computers. (e.g. Microsoft
Windows, Linux, Mac OS)
Operating System
It manages the database within the database system. (e.g.
Microsoft SQL Server, Oracle, MySQL)
DBMS Software
They are used to access and
manipulate data in the DBMS and to manage the computer environment in
which data access and manipulation take place. (e.g. Adobe Dreamweaver,
Microsoft Visual Studio, WAMPServer, XAMPP and Laragon)
Application Programs and Utility Software
This component includes all users of the database system. On the basis of job
functions
Users
They oversee the database system’s general
operations.
System Administrators
Also known as DBAs, they manage the DBMS and
ensure that the database is functioning properly to avoid system glitches in the
future.
Database Administrators
They simply design the database structure that will
dictate the usefulness and effectiveness of the database environment that these
people will develop
Database Designers
They design and implement the
application programs. They also design and create the data – entry screens,
reports, and procedures through which end – users access and manipulate the
database’s data.
Systems Analysts and Programmers
These are the people who use the application programs to run
the organization’s daily operations.
End – users
These are the instructions and rules that govern the design and use of
the database system.
Producers
This refers to the collection of facts stored in the database. Because data are
the raw material from which information is gathered, determining what data to enter
into the database and how to organize those data is a vital part of the database
designer’s job.
Data
