CH 1: Database Environment and Development Process Flashcards
(22 cards)
What is a database?
Organized collection of logically related data
Databases are designed to store, manage, and retrieve data efficiently.
Define structured data.
Stored representation of meaningful objects and events in formats like numbers, text, dates
Structured data is easily searchable and organized.
Define unstructured data.
Stored representation of meaningful objects and events in formats like images, video, documents
Unstructured data is more complex and harder to analyze.
What is metadata?
Data that describes the properties and context of user data
Metadata provides information about other data.
What are flat files?
Files that contain records stored sequentially or indexed for processing
Flat files can be sequential, indexed sequential, or direct.
What is a record?
A collection of related fields
Records represent a single entry in a database or file.
Fill in the blank: A __________ is a collection of related records.
File
What is file organization?
The ways in which records are physically stored on a device and retrieved
File organization affects data access speed and efficiency.
What is program-data dependence?
All programs maintain metadata for each file they use
This can lead to issues with data management and maintenance.
List three disadvantages of file processing.
- Problems with data dependency
- Duplication of data
- Data inconsistency
What is data redundancy?
Having duplicate copies of the same data across different systems or programs
Data redundancy can lead to increased maintenance costs and data inconsistency.
What is a database management system (DBMS)?
Software for creation and management of the database
A DBMS facilitates the efficient handling of data.
What are the advantages of databases?
- Little data redundancy
- Data sharing
- Program-data independence
- Improved data quality
- Reduced program maintenance
What is the biggest problem with data redundancy?
Data changes in one file could cause inconsistencies
This compromises data integrity.
What is the hierarchical model in database organization?
Data is stored as a binary tree model with records in nodes
In this model, sub-nodes represent relationships between records.
What is the relational model?
Data is stored as a two-dimensional table with rows and columns
Each row represents a record, and each column represents a field.
Define conceptual schema.
Entity-relationship model produced during the database life cycle design
It outlines the structure and relationships of data.
What is the purpose of the analysis phase in SDLC?
Thorough requirements analysis and structuring
The deliverable is functional system specifications.
What is the maintenance phase in SDLC?
Monitor, repair, and enhance the system
It includes periodic audits and performance analysis.
What is prototyping in database development?
Rapid application development using initial prototype versions
This allows for iterative improvements based on user feedback.
True or False: Databases require less time spent in maintenance compared to flat files.
True
What is the external schema?
How data looks to a particular user
It defines user views of the database.
