DBSM 110 Midterm
The storage manager components includes:
*File manager *Buffer manager *Authorization and integrity manager *Transaction manager
In what decade did the type of data stored in a database evolve.
2000
Advanced phases of normal form includes:
4NF BCNF DKNF PJNF
An instance can be defined as: A design of a database
A collection of information stored in the database at a particular moment
A database management system (DBMS) is
A collection of interrelated data and set of programs used to access data
What are the some of the rules of second normal form?
A database most be in first normal A relation must not contain any partial dependency Each table must contain data about one type of thing
What is a composite primary key?
A primary key consisting of two or more attributes that uniquely identifies each row
What is normalization?
A process used to reduce data redundancy in relational database
A query is:
A statement used to retrieve information for the database.
A composite table:
A table used to link two or more entities participating in a M:N relationship
A relationship is:
An association among one or more entities
Responsibilities of Database Administrators includes:
Applying schema and physical organization modification Defining the storage structure and access method definition Defining the schema definition
The three properties of transaction management discussed in this book are:
Atomicity, Consistency, Durability
The actual physical backup files are known as:
Backupsets
Which type of key represents a minimal subset of super key?
Candidate Key
Foreign keys helps ensure that the data stored in the database is:
Consistent and Valid
What are the two states in which backups can be taken
Consistent and inconsistent
What language would you use to specify the storage structure of a database schema?
DDL
What are the two languages a database system provides?
DDL and DML
What data structures does the storage manager implement?
Data files, Data Dictionary, Indices
What are the some of the rules of third normal form?
Data must be in second normal form Data most have no transitive dependency
What happens if a database is not normalized?
Data redundancy
What does the management of data involve?
Defining structures for storage of information and providing mechanism for manipulating data.
Functional dependency can:
Determine the value of the dependent attribute
Some of the disadvantage of keeping information in a file-processing system are:
Difficulty accessing the data Data redundancy and inconsistency Security problems Data isolation
The set of permitted values allowed to be stored in a column is known as:
Domain
Who does the database designer have to interact with to understand the needs of the application?
Domain experts and Users
Each attribute has a set of permitted values known as:
Domain or value set
What is a domain constraint?
Domains that specify possible values that can be store in an attribute
An Entity Relational Diagram consist of the following components used to define a database schema
Entities, attributes, relationship
What are business rules used to define?
Entities, attributes, relationships, and constraints
An Entity Diagram is used to:
Express the overall logical structure of a database graphically
Data is organized facts.
False
Data redundancy anomalies are encountered when the same data is stored in multiple database.
False
Normalization only contains three phases.
False
The earliest database system arose in 1980s
False
There are six types of data anomalies?
False
Business Rules constraints falls into two categories:
Field and relationship
What is the initial phase of database design?
Fully characterize the data needs of the prospective database users.
The extended version of an ER uses which of the following features:
Generalization Specialization (Attribute inheritance) Aggregation
The goal of normalization is to:
Generate a set of relation schemas that allows us to store information without unnecessary redundancy
What is the role of data abstraction in a database?
Hide the complexity of storing data from the user.
What was the first relational database product?
IBM System R
When is a domain consider to be in an atomic state?
If the element of a domain is considered indivisible
How is query language categorized?
Imperative query language Declarative query language Functional query language
What type of anomalies results from data redundancy?
Insertion, Update, Deletion
Data types are used to help enforce the domain of a column. Select the common types of datatypes.
Integers Boolean Floats
Relational algebra consist of set of operations including:
Join Cartesian Product Project Rename Select
Select the operation that allows us to combine a selection and a Cartesian product into a single operation?
Join Operation
Data Integrity refers to:
Maintaining the quality of the data stored in the database.
Normalization will:
Minimize data redundancy
The types of database users are:
Naïve Sophisticated user Programmers
Transitive functional dependency occurs when:
One or more non key attributes has a dependency on another super key attribute that was not chosen as a member of the primary key.
What are the types of relationships exist within a relational database design?
One to Many One to One Many to Many
Data security consist of:
Only the people who should have access to the data are the only ones who can access the data Protection of data Prevention of data corruption Authentication/authorization, encryption, and masking are some of the popular means of data security Ensure that data is accessed by its intended user
What are the type of participation available in an entity set relationship?
Partial Total
What are applications?
Programs that are used to interact with the database
Using ERD Chen Notation entities are represented using:
Rectangle
A referential integrity constraint requires:
Requires that the values appearing in specified attributes of any tuple in the referencing relation also appear in the specified attributes of at least one of tuple in the referenced relation.
How can a database schema be depicted?
Schema diagram
In which normal form does an attribute that is not fully dependent on the primary key is split into a separate table.
Second Normal
Which type is key consist of a set of one or more attributes that collectively identify uniquely a tuple in the relation?
Super Key
A relational database consist of a collection of:
Tables
As it relates to functional dependency, what does the equation "A,B --> C" represents?
The combination of values in columns A and B determines the value of column C
What does a database design involve?
The design of a database schema
A database model is a set of entities and relationships that exist in the real world.
True
A functional dependency is like a partial key: It uniquely determines the value for some attributes but not all in general.
True
A null value signifies that the data is unknown or doesn't exist.
True
A query language is a language in which a user can request information from the database.
True
A transaction is a collection of operations that performs a single logical function in a database application.
True
A tuple is simply a sequence of values.
True
A variety of new data-intensive applications and the need for rapid development lead to NoSQL database.
True
An "attribute" refers to the heading of a column.
True
An attribute takes a null value when an entity does not have a value for it
True
An attribute that contains the firstname, lastname, and middle name would be considered as having multiple values.
True
An entity has a set of properties known as attributes.
True
An entity is a thing or object in the real world that is distinguishable from other object.
True
An entity/table consists of a set of related attributes/columns that is used to organize data for the purpose of providing meaningful information to the end users.
True
Data can be used to transform raw facts into information, and information can be used to acquire knowledge.
True
Data models can be classified into four categories.
True
Data redundancy leads to repetition of data hence extra space is required and anomalies are encountered.
True
ERD Notation represents a complete set of work flow shapes & symbols used in the graphical representation of data.
True
In first normal form each field should contain a single (atomic) item
True
Information processing drives the growth of computers.
True
It is good practice have the foreign key reference an existing primary key in the table being referenced. Correct! True
True
When designing database schemas we must ensure that we avoid redundancy and incompleteness.
True
You should identify the PK in first normal form
True
Relational algebra consist of a set of operation that takes one or two relations as input and produce a new relation as a result. Select the two categories which the set operations are grouped into.
Unary, Binary
An entity whose existence is dependent on another entity is known as:
Weak Entity
Existence dependence occurs on
Weak Entity
Functional Dependency occurs:
When a non-key attributes exhibits a dependency on one or more super key attributes.
When does a relationship exist between entities?
When an attribute of one entity refers to an attribute in another entity
Does each DBMS has its own architecture for handling transaction log files?
Yes
Business Rules describe the _________ policies that apply to the data stored on a company's database.
business
Specialization is
the process of designating subgroupings within an entity