Database Management Test 2 MC

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The basic SQL vocabulary has fewer than ___ words

100

A table that has all key attributes defined, no repeating groups, and all its attributes are dependent on the primary key is said to be in ___

1NF

All relational tables satisfy the ___ requirements

1NF

From a structural point of view, 2NF is better than

1NF

Data warehouse routinely uses ___ structures in its complex, multilevel, multisource data environment

2NF

From a structural point of view, 3NF is better than ___

2NF

A table that is in 2NF and contains no transitive dependencies is said to be in ___

3NF

A table where all attributes are dependent on the primary key but are independent of each other, and no row contains two or more multivalued facts about an entity is said to be in ___

4NF

In the ___, no row may contain two or more multivalued facts about an entity

4NF

Some very specialized applications may require normalization beyond the ___

4NF

All changes in a table structure are made using the ___ TABLE command

ALTER

The ___ SQL standards are also accepted by the ISO

ANSI

___ is the process the DBMS uses to verify that only registered users access the database

Authentication

U.S. state abbreviations are always two characters, so ___(2) is a logical choice for the data type representing a state column

CHAR

The ___ constraint is used to validate data when an attribute value is entered

CHECK

The SQL command that allows a user to permanently save data changes is ___

COMMIT

The ___ permanently saves all changes

COMMIT

Using the ___ command, SQL indexes can be created on the basis of any selected attribute

CREATE INDEX

When designing a new database structure based on the business requirements of the end users, the database designer will construct a data model using a technique such as ___

Crow's Foot notation ERDs

The ___ command defines a default value for a column when no value is given

DEFAULT

What command is used to delete a table row?

DELETE FROM tablename WHERE condition

A table can be deleted from the database by using the ___ TABLE command

DROP

To delete an index, one must use the ___ INDEX command

DROP

___ databases reflect the ever-growing demand for greater scope and depth in the data on which decision support systems increasingly rely

Data warehouse

If a designer wishes to create an inner join, but the two tables do not have a commonly named attribute, they can use a ___ clause

JOIN ON

The SQL data type DATE stores dates in the ___ date format

Julian

If a user adds a new column to a table that already has rows, the existing rows will default to a value of ___ for the new column

NULL

___ is a process to help reduce the likelihood of data anomalies

Normalization

If the database tables are treated as though they were files in a file system, the ___ never has a chance to demonstrate its superior data-handling capabilities

RDBMS

The ___ command is used to restore the database to its previous condition

ROLLBACK

Which SQL format would be best used for a small, numeric data type?

SMALLINT

When a user issues the DELETE FROM tablename command without specifying a WHERE condition, ___

all rows will be deleted

An attribute that cannot be further subdivided is said to display ___

atomicity

Improving ___ leads to more flexible queries

atomicity

The tables on which a view, or virtual table derived from a SELECT query, are based are called ___ tables

base

A ____ routine pools multiple transactions into a single batch to update a master table field in a single operation

batch update

BCNF can be violated only if the table contains more than one ___ key

candidate

An alias ___ be used when a table is required to be joined to itself in a recursive query

cannot

An atomic attribute ___

cannot be further subdivided

The ___ is central to a discussion of normalization

concept of keys

A ___ join performs a relational product (also known as the Cartesian product) of two tables

cross

The price paid for increased performance through denormalization is a larger amount of

data redundancy

In order to meet performance requirements, portions of the database design may need to be occasionally ___

denormalized

Any attribute whose value determines other values within a row is known as a ___

determinant

Attribute A ___ attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B

determines

When you create a new database, the RDBMS automatically creates the data ___ in which to store the metadata and creates a default database administrator

dictionary

Repeating groups must be eliminated by ensuring that ___

each row defines a single entity

The objective of normalization is to ___

ensure that each table conforms to the concept of well-formed relations

According to the data-modeling checklist, ___ should be nouns that are familiar to business, should be short and meaningful, and should document abbreviations, synonyms, and aliases for each entity.

entity names

In the context of partial dependencies, data redundancies occur because ___

every row entry requires duplication of data

___ refers to the level of detail represented by the values stored in a table's row

granularity

A common practice is to create an ___ on any field that is used as a search key, in comparison operations in a conditional expression, or when a user wants to list rows in a specific order

index

When using an ___ join, only rows from the tables that match on a common value are returned

inner

A table is in 4NF if it is in 3NF, and ___

it has no multivalued dependencies

A table is in fourth normal form if

it is in third normal form and has no independent multivalued dependences

An ERD is created through an ___ process

iterative

The ___ condition is generally composed of an equality comparison between the foreign key and primary key of related tables

join

Denormalization produces a ___ normal form

lower

Normalization represents a ___ view of the entities within the ERD

micro

In a ___ situation, one key determines multiple values of two other attributes and those attributes are independent of each other

multivalued dependency

In an INSERT command, a user can indicate just the attributes that have required values by listing the ___ inside parentheses after the table name

names

A ___ join will select only the rows with matching values in the common attributes

natural

Normalization works through a series of stages called ___

normal forms

In a 1:M relationship, a user must always create the table for the ___ side first

one

An ___ join returns not only the rows matching the join condition, but also the rows with unmatched values

outer

When writing SQL table-creating command sequences, the entire table definition is enclosed in ___

parenthesis ()

Dependencies based on only a part of a composite primary key are known as ___ dependencies

partial

If a table has multiple candidate keys and one of those candidate keys is a composite key, the table can have ___ based on this composite candidate key even when the primary key chosen is a single attribute

partial dependencies

A dependency based on only a part of a composite primary key is called a

partial dependency

In order to meet ___ requirements, you may have to denormalize some portions of a database design

performance

A table whose ___ key consists of only a single attribute is automatically in 2NF once it is in 1NF

primary

An attribute that is part of a key is known as a ___ attribute

prime

In the SQL environment, the word ___ covers both questions and actions

query

To make the SQL code more ___, most SQL programmers use one line per column (attribute) definition

readable

An alias is especially useful when a table must be joined to itself in a ___ query

recursive

You cannot have an invalid entry in the foreign key column; at the same time, you cannot delete a vendor row as long as a product row references that vendor. This is known as ___

referential integrity

A ___ derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence

repeating group

A relational table must not contain a ___

repeating group

Words used by a system that cannot be used for any other purpose are called ___ words

reserved

___ words are words used by SQL to perform specific functions

reserved

The SQL data manipulation command HAVING:

restricts the selection of grouped rows based on a condition

A ___ is a logical group of database objects, such as tables and indexes, that are related to each other

schema

The CREATE TABLE command lets you define constraints when you use the CONSTRAINT keyword, known as a ___ constraint

table

When a table contains only one candidate key, ___ are considered to be equivalent

the 3NF and the BCNF

Normalization works through a series of stages called normal forms. For most purposes in business database design, ___ stages are as high as you need to go in the normalization process

three

A ___ exists when there are functional dependencies such that Y is functionally dependent on X, Z is functionally dependent on Y, and X is the primary key

transitive dependency

It is possible for a table in 2NF to exhibit ___, where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes

transitive dependency

An ___ view is a view that can be used to update attributes in the base tables that are used in the view

updatable

A ___-length character data type, like VARCHAR, is usually specified with a maximum length

variable

Unnormalized tables yield no simple strategies for creating virtual tables known as ___

views

A view is a ___ based on a SELECT query

virtual table


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