If a foreign key contains either matching values or nulls, the tables that make use of such a foreign key are said to exhibit ________ integrity.
referential
entity
secondary
restrictive
Nulls, if used improperly, can create problems because they can represent __________.
a missing attribute value
a default value
an unsortable attribute value
a zero
How is a strong relationship depicted in a Crow's Foot ERD?
no line
solid line
dotted line
double line
Relational Database model was proposed by?
Larry Ellison
Bill Gates
P. Chan
E. F. Codd
BCNF is an extension of 3NF.
Repeating groups are eliminated in
1NF
2NF
3NF
BCNF
Relational databases follow ACID transactions. They do not allow multiple transactions occuring at the same time to impact each others execution. This particular characteristic of ACID is called ________
Atomicity
Consistency
Isolation
Durability
In a relationship, when a primary key from one table is also defined in a second table, the field is referred to as a ______ in a second table.
foreign key
composite key
super key
primary key
Supertype can have many subtypes.
Which one of the following is NOT part of ensuring 1NF?
Remove repeating groups
Remove partial dependencies
Remove multi-valued attributes
Establish a primary key
Which of the following type(s) of attributes need not be physically stored within the database?
Multivalued
Composite
Derived
None of the above
What is an advantage of a DBMS?
Data security
Data sharing
Data access
Data backup
All of the above
Entity supertypes and subtypes are organized in a(n) ______.
overlapping hierarchy
specialization hierarchy
linear hierarchy
generalization hierarchy
Big data is a collection of datasets so large and complex that it becomes difficult to process using traditional database management tools or data processing applications.
All databases must meet
4NF
Which one of the following is NOT true about a null value?
An unknown attribute value
A known, but missing, attribute value
An inapplicable condition
A value equal to zero
An Insert Anomaly occurs when certain attributes are inserted into the database without the presence of other attributes.
Which one of the following is NOT mentioned in the Gartner's definition of big data?
Volume
Variety
Veracity
Velocity
The ______ adds support for entity supertypes, subtypes, and entity clustering.
object-oriented model
extended entity-relationship model
relational model
hierarchical entity model
Which of the following is NOT an example of a multivalued attribute?
A person's social security number
Degree(s) held by a person
A car's color(s)
Phone number(s) in a household
___________________ means that every supertype occurence must be a member of at least one subtype.
Total subtypes
Partial completeness
Specialization subtypes
Total completeness
An entity in the logical design becomes a ________ in the corresponding physical design.
database
table
attribute
relationship
Which one of the following is NOT a relational database?
SQL Server
Oracle
MySQL
MongoDB
____________________ is a field that can have many values for a single entity occurence.
multivalued attribute
multivalued entity
null
repeating group
Each table must have a ___________ key.
primary
foreign
domain
composite
An attribute or a combination of attributes that uniquely identifies any given row is called ____________.
Referential integrity means that, if the foreign key contains a value, that value refers to an existing valid tuple (row) in another relation.
A surrogate primary key is an "artificial" primary key that is used to uniquely identify each entity occurrence when there is no good natural key available.
How would you graphically identify an entity in a Crow's Foot model ERD?
a line
a square
a rectange
a diamond
About 80% of all data are believed to be in unstructured form.
CAP Theorem allows multiple user views in relational databases.
As a general rule, a ______________ in a business rule will translate into a(n) ___________ in the model, and a(n) ___________ associating nouns will translate into a(n) ___________ among the entities.
verb, entity, noun, relationship
noun, entity, verb, relationship
noun, relationship, verb, entity
verb, relationship, noun, entity
Which of the following is true of business rules?
They allow the designer to set company policies with regard to data.
They allow the designer to develop business processes.
They can serve as a communication tool between the users and designers.
They provide a framework for the company's self-actualization.
A(n) is a restriction placed on the data.
constraint
