Chapter 2 Flashcards
3 Vs
Volume: amount of data
Variety: numbers of type of data
Velocity: speed of data access
American National Standards Institute (ANSI)
The Institute oversees the creation, promulgation and use of thousands of norms and guidelines. Defined a framework for data modeling based on degrees of abstraction in the early 1970’s
Attrbiute
A characteristic of an entity
Business rule
Description of a policy, procedure, or principle within a specific organization
Conceptual model
Global view of the entire database as viewed by the entire organization
Conceptual schema
Basis for the identification of the high-level description of the main data objects. ER model most widely used
Connectivity
Labels relationship types in an ER model
Entity
A person, place, or thing that is collected data on
Entity instance
Each row in a relational table
Entity relationship (ER) model
Graphical model which represents entities and their relationship
Entity relationship diagram (ERD)
ER models displaying database components
Entity set
A collection of like entities
Extended relational data model (ERDM)
Adds many OO model features to relational database structure such as encapsulation, inheritance, and extensible data types
External schema
A specific representation of an external view
External model
The end user’s view of the data environment
Hadoop
Open source, Java-based programming framework that supports the processing and storage of extremely large data sets in a distributed computing environment
Hierarchical model
Developed to manage large amounts of data for complex manufacturing projects.
Internal model
Representation of the database as seen by the DBMS
Internal schema
Depicts a specific representation of an internal model
Logical design
The task of creating a conceptual design that could b implemented in any DBMS
Logical independence
Being able to change the internal model without affecting the conceptual model
Object-oriented data model (OODM)
Both the data and relationships are contained in a single structure called an object
Semantic data model
A model which describes the meaning of its instances
Network model
user perceives the network database as a collection of record in 1:M relationships
Schema
conceptual organization of the entire database as viewed by the database administrator
Subschema
Portion of the database seen by the application programs that actually produce the desired information from the data contained withing the database
Relation
Matrix composed if intersecting rows and columns. Commonly called a table
Tuple
Each row in a relation
Unified Modeling Language (UML)
language based on OO concepts that describes a set of diagrams and symbols that can be used to graphically model a system
