ANSWER GUARANTEE A+ 2025/2026
five advantages of databases - 1. reduce redundancy
2. increase information quality
3. flexibility
4. increase information security
5. scalability
relational integrity constraint - rule that enforces basic and fundamental
information-based constraints (ensure accuracy and consistency of data)
business-critical integrity constraint - rule that enforce business rules vital
to an organization's success and often require more insight and knowledge
than relational integrity constraints
password - provides authentication of the user
access level - determines who has access to the different types of
information
access control - determines types of user access, such as read-only
access
entity - object, concept or event (subject)
ex. Customer
attributes - a characteristic of an entity
ex. Customer ID, Customer Name, Contact Name, Phone #
record - the specific characteristics of one entity also called a row or tuple
ex. 314-882-2409 or David Logan
A representation of an entity in a meaningful way, which includes the
attributes of the entity, is called a ________.
table - a collection of records
,ex. all the information
database - a collection of tables
stores info for a single application
primary key - indicates uniqueness within records or rows in a table
foreign key - the primary key from another table, this is the only way join
relationships can be established
The Entity Relationship (ER) Model - forms the basis of an ER diagram
ERD (entity relationship diagram) - represents conceptual database as
viewed by end user
depicts: entities, attributes, and relationships
cardinality - the count of records that are allowed or are necessary between
entity relationship
tells us how many rows we need from one table before we can link it to
another table
"number of elements of the set"
Structured query language (SQL) - uses queries to retrieve records, insert
and edit data, and delete records.
widely used to manipulate information in relational databases
IVR - interactive voice response
null value - cases where an attribute does not have an applicable value for
an attribute
never allowed in KEY fields
derived attribute - if an attribute can be calculated using the value of
another attribute
, not stored in the file, but can be ___________ when needed from the
stored attributes
stored attributes - the attribute that is used to derive the attribute
composite attributes - can be divided into smaller subparts, which represent
more basic attributes that have their own meanings
ex. Address
-can be broken down into a number of subparts, such as street, city, state,
zip code
simple attributes - cannot be divisible into subparts
data dictionary - stores definitions of information types, identifies the
primary and foreign keys, and maintains the relationships among the
tables.
database administrator (DBA) - the role may include capacity planning,
installation, configuration, database design, migration, performance
monitoring, security, troubleshooting, as well as backup and data recovery
big data - an accumulation of data from:
company employees entering data
users entering their own data
machines/computers are accumulating data
collections of data that are so enormous in size, so varied in content, and
so fast to accumulate that they are difficult to store and analyze transitional
approaches
parallel processing - so much data is being generated that it can't load the
dataset on one computer, server. In order to compensate we use this
hadoop - an open source platform, allows parallel processing of big data
created by doug cutting
MapReduce - provides a table of contents for our data