Quiz 1 - Part 2 Flashcards
Abstraction of a real-world object or event
Model
Simple representations of complex real-world data structures
Data models
represents data structures and their characteristics, relations, constraints, transformations, and other constructs with the purpose of supporting a specific problem domain
Data Models
Iterative and progressive process of creating a specific data model for a determined problem domain
Data modeling
An implementation-ready data model should contain a description of the data structure that will store…
the end-user data
An implementation-ready data model should contain a set of enforceable rules to guarantee…
the integrity of the data
An implementation-ready data model should contain a data manipulation methodology to support …
the real-world data transformations.
Importance: Data models are a …. tool
communication
Importance: Data models give an overall….
view of the database
Importance: Data models organize… for various users
data
Importance: Data models are an abstraction for the creation of g…. d…..
good database
Unique and distinct object used to collect and store data
Entity
A person, place, thing or event about which data will be collected and stored
Entity
Characteristic of an entity
Attribute
Describes an association among entities
Relationship
Set of rules to ensure data integrity
Constraint
Brief, precise, and unambiguous description of a policy, procedure, or principle
Business Rule
Business Rules enable defining the basic…
building blocks
Describe main and distinguishing characteristics of the data
Business Rule
Business rules must be rendered in …. and must be kept….
writing/ up to date
Business rules sometimes are … to the organization
external
Business rules must be easy to u…. and widely d…..
understand / disseminated
Business rules describe characteristics of the data as …. by the company
view
Company managers, policy makers, department managers, written documentation and direct interview with end users are…
sources of business rules
Business rules help standardize…
company’s view of data
Business rules create …. between users and designers
communications tool
Business rules allow designer to understand the … , …. , …. of data, and …. processes
nature/role/scope/business
Business rules allow designer to develop appropriate r….. participation rules and c….
relationship/ constrains
Business rules allow designer to create an accurate….
data model
Nouns translate into…
entities
Verb translate into… among entities
relationship
Relationships are b…
bidirectional
Conceptual organization of the entire database as viewed by the database administrator (whole database)
Schema
Portion of the database seen by the application programs that produce the desired information from the data within the database (part of database)
Subschema
Environment in which data can be managed and is used to work with the data in the database. SELECT,UPDATE, INSERT
Data manipulation language
Enables the database administrator to define the schema components . CREATE, DROP, RENAME, TRUNCATE
Schema data definition language
Based on a relation. Related to each other through sharing a common entity characteristic
The Relational Model
The Relational Model describe a precise set of d…. m…. constructs
data manipulation
Relational table is purely l…. s…..
logical structure
Structural independence is promoted using i…. t…..
independent tables
…. view improves conceptual simplicity
Tabular
Ad hoc query capability is based on….
SQL
Relational models Isolate the end-user from … details
physical-level
Relational models improve i…. and m…… s………
implementation / management simplicity
Relational model requires h…. and system s…… overhead
hardward / softward
Conceptual simplicity gives untrained people the tools to use a g….. s….. p….
good system poorly
Uses graphic representations to model database components
Entity relationship diagram (ERD)
For ERD , an entity is mapped to a …..
relational table
Entity instance or occurrence is …. in table
row
Entity set is a collection of ….
like entities
Connectivity lables types of….
relationships
Entity relationship models with visuals yield conceptual s…
simplicity
Entity relationship models with visuals make them effective… tool
communication
Entity relation models are integrated with the dominant r…… m….
relational model
Entity relationship models have limited c……. representation
constraint
Entity relationship models have limited r……. representation
relationship
Entity relationship models lose i……. content when a….. are removed from entities to avoid crowded displays.
information / attributes
K…….. data model is based on a structure composed of two data elements: a key and a value, in which every key has a corresponding value or set of values.
key-value
NoSQL Database are not base on the r…….. m………
relational model
NoSQL databases support distributed d……. a…….
database arquitectures
NoSQL Databases provide high s……., high a……, and fault t……
scalability / availability / tolerance
NoSQL support ….. amounts of sparse data
large
NoSQL database geared toward p….. rather than t….. c……
performance / transaction consistency
Each row represents one entity instance - relational or key-value model
relational model
Each column represents on attribute of the entity - relational or key-value model
relational model
the values in a column are of the same data type - relational or key-value model
relational model
Each row represents on attribute/value of one entity instance - relational or key-value model
key-value model
the “ key” column could represent any entity’s attribute - relational or key-value model
key-value model
The values in the “value column could be of any data- type and therefore it is generally assigned a long string data type - relational or key-value model
key-value model
NoSQL provide high s…., a……., and fault t…. are provided
scalability/ availability/ tolerance
NoSQL uses l…. commodity hardware
low-cost
NoSQL supports B…. D…
big data
For NoSQL, key-value model improves s….. e…..
storage efficiency
For NoSQL, c……. programming is required
complex
For NoSQL, there is no r………. s…….
relationship support
For NoSQL, there is no i…… s……
integrity support
Conceptual Model to Internal Model is …. independence
logical
Internal Model to Physical model is ….. independence
physical
E…… R……. is the most abstract model
ENTITY RELATIONSHIP
R…. model is a medium abstract model
Relational
End users’ view of the data environment
external model
Represents a global view of the entire database by the entire organization
Conceptual model
Representing database as seen by the DBMS mapping conceptual model to the DBMS
Internal model
Describes the way data are saved on storage media such as disks or tapes
Physical model
models Independent of hardward and softward
External and conceptual models
models independent of hardware only
internal model
model independent of neither hardware nor software
Physical