[Working] C175 C170 Data Management Foundations Study Guide (Download To Score An A)

Data Management Foundations Study Guide C175

14% Lesson 1 Introduction to Databases, Information and Data
(7 Questions)

Competency 4017.1.1: Introduction to Information and Data
Explain how data, databases, and data management is used in today's organization
 Explain what data is and how is it stored
 Explain the different types of data
 Define file structures
 Explain how data was stored and retrieved before the use of database
management systems

1.1 Why Databases
 Best way to store and manage data
 Makes data persistent and shareable in a secure way
 Essential for organizations to know information about Customers, Products,
Employees, Debtors / Creditors
 Helps organizations use data / information as a resource to make
decisions

1.2 File Structures
 File-Based (Prior to DBMS)
o Attempt to computerize old manual filing system
o Was easy to retrieve small amounts of information from
o As data grew, it became difficult to locate and retrieve information
o Retrieval speed depended on file structure and how data was
organized within the structure

 File types utilized in a file-based system
o Flat Files
 No internal hierarchy
 Plain text or Binary files
 Data that is unstructured
 Uses a lot of computer memory to access, edit, and rewrite files
after use

o Heap Files
 Unsorted set of records
 Uniquely identified by record ID




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, Data Management Foundations Study Guide C175




o Allows Heap file to be inserted or deleted using ID
o Index Files
 File that stores a list of Look Up Field values from data file
that includes the location (address) in the data file of the
corresponding record
 Smaller than the entire record, usually fits in main memory for
quick look up
 Lists keywords and phrases that are in a particular file
 Becomes a pointer to the location in the file where the
information can be found when stored with keywords and
phrases




o Hashed Files
 Uses hash functions to decide where records should be placed
on a disk
 Allows for faster data look up without the use of an index file

1.3 Data versus Information
 Data
o Data is the Foundation of Information
o Consists of Raw Facts not yet processed to reveal meaning
o Raw facts / data will need to be transformed to better understand what
it is that you have
o Must be properly formatted for storage, processing, and presentation

 Information
o Information is the Bedrock of Knowledge
o Produced by Processing Raw Data to reveal its meaning



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, Data Management Foundations Study Guide C175

 Processing may be as simple as organizing it to reveal patterns
or complex as making forecast / drawing inferences using
system statistical modeling
o Key to good decision making and business survival is accurate,
relevant, and timely information

 Knowledge
o Information and facts about a specific subject
o Implies familiarity awareness and understanding of Information
o Key Characteristic is that New Knowledge can be derived from Old
Knowledge
 Data Management
o A discipline that focuses on the proper generation, storage, and
retrieval of data
o Is it core activity for any business, government agency, service
organization, or charity

1.4 Introducing the Database
 Database
o Shared, integrated computer structure that stores:
 End User Data
o Raw facts of interest to the end user

 Metadata (Also called: A collection of Self-Describing Data)
o Data about data through which data is integrated and
managed
o Describes data characteristics and set of relationships
that links data found in the database
o Stores information like:
 Name of each data element
 Type of values (numeric, dates, or text) on each
data element
 Whether the data element can be left empty
o Complements and expands the value and use of the data

 Role of the DBMS
o An intermediary between user and database
o Presents the end user with a single integrated view of data in a
database
o Receives all application requests and translates them into
complex operations
o Hides database complexities from the application programs and users
o Provides a framework facilitate data quality initiatives



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, Data Management Foundations Study Guide C175

o May be written using Visual Basic, NET, JAVA, C#, or through a DBMS
utility program




 Advantages of a DBMS
o Enables data sharing across multiple applications / users
o Integrates different user views of data into a single repository
o Makes data management more efficient and effective

o Improves Data Sharing
 Creates an environment in which users have better access two
more and better-managed data

o Improves Data Security
 Provides framework for better enforcement of data / security
policies

o Better Data Integration
 Promotes integrated view of operations and the ability to see
data relations or impact actions have in other areas

o Minimizes Data Inconsistency
 Data Inconsistency exists when different versions of the
same data appear in different places
 Greatly reduced in a properly designed database

o Improves Data Access
 Easier to produce quick answers to a query / ad hoc query
o Query is a specific request / question
o Ad Hoc Query is a “Spur-or-the-Moment” question
o Query Result Set is a collection of data rows returned by
a query

o Improves Decision Making


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