Exam 1 LIS 464

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Which of the following relationship types is the most common according to Hernandez? 1:M 0:1 M:N 1:1

1:M

Which of the attributes in Entity X should be copied into Entity Y to create a relationship between the two tables? B D A C

A

Which of the following is NOT a data structure _within an SQL database_ as described by Hernandez. Foreign Keys Primary Keys Arrays Fields Tables

Arrays

Which of the following is NOT a step in analyzing the current database? Identify and analyze reports Correct errors in the current database as you go. Examine how data is collected Identify current information needs Identify future information needs Make a list of possible fields

Correct errors in the current database as you go.

Which is a valid CREATE TABLE statement? Create table emp add(id integer(3)); Create table emp (id integers(3)); Create table emp (id int); Create table emp modified (id integer(3));

Create table emp (id int);

Which of the following keyword can be used to select unique values from a column? Distinct Unique Distinguished nonduplicate

Distinct

"Degree of participation" in relationships refers to how completely the database management system software supports that type of relationship. True False

False

A "data table" stores data in a database to supply information for queries. True False

False

A composite key is a group of attributes that uniquely identifies a row. True False

False

A foreign key is one or more columns in one table that uniquely identifies the rows in that table. True False

False

A null has the same effect on a calculation or aggregation function as a blank space True False

False

A surrogate key is a key drawn from existing fields describing the data in the database. True False

False

Degree of participation indicates the attribute type that a record must associate with in a related table. True False

False

SQL stands for Standard Query Language. True False

False

The physical order in which data appear within a table is important. True False

False

The term "primary key" and "index" are synonyms in database design. True False

False

SQL statements end with a colon. True False

False (semicolon)

Which of the following items is not a critical concept in relational database model? Select all that apply. Record Table Feature Entity Relationship

Feature

Which SQL statement inserts data into a table called Projects? INSERT Projects ('Content Development', 'Website content development project') SAVE INTO Projects (ProjectName, ProjectDescription) VALUES ('Content Development', 'Website content development project') INSERT INTO Projects (ProjectName, ProjectDescription) VALUES ('Content Development', 'Website content development project')

INSERT INTO Projects (ProjectName, ProjectDescription) VALUES ('Content Development', 'Website content development project')

which of the following is NOT a phase of database design according to Hernandez Determine and establish table relationships Define a mission statement and objectives Implement the design in software Review data integrity

Implement the design in software

Which of the following SQL keyword is used to add data to a table? Drop Add Add Row Insert

Insert

According to the textbook, the only appropriate reason to have a duplicate field across tables is: It is used to link tables together through PK/FK pairs It provides supplemental information It indiciates multiple occuraences of a particular value It indicates a larger degree of participation in a relationship

It is used to link tables together through PK/FK pairs

Which SQL term is typically used with SQL wildcard operators? AS ANY @ LIKE

LIKE

According to Hernandez Chapter 4, business rules are best described as: The requirement to avoid multivalued attributes Limitations and requirements that you build into the database The requirement that you follow the complete design process Decisions made by the company based on the analysis of the database's data

Limitations and requirements that you build into the database

Which of the following is not an advantage of good database design listed by Hernandez? Lower costs Data integrity Independence from specific software Easy retrieval

Lower costs

You are given an E-R diagram with two entities, ORDER and CUSTOMER, as shown below, and are asked to revise the relationship between them based on new information. The new information is that "A given customer can place many orders and a given order can be placed by one or more customers." Whiich of the following should be the relationship type in the revised model? 1:N N:1 N:M 1:1

N:M

Which of the following database types is used predominately with active, dynamic data such as data produced by an online ordering system? OLDA online data analysis database OLTP online transaction processing database OLAP online analytical database OSAP online systems processing database

OLTP online transaction processing database

Where should the foreign key most traditionally be located in the following one to many ERD? Option A Option B None of the above Option C Option D

Option D

Based on the tables show below, would you say the relationship between SALES REP and CUSTOMER is optional or mandatory? GENERAL SALES DATABASE: SALESREP SalesRepNo RepName HireDate CUSTOMER CustNo CustName Balance SalesRepNo Neither Optional Nor Mandatory Mandatory Both Optional and Mandatory Optional

Optional

Which deletion rule does Hernandez suggest as your default choice when considering deleting a record in a parent/child table relationship? (unless you specifically design otherwise) Restrict Nullify Cascade Deny Set Default

Restrict

Based on the tables below, which of the following SQL commands would return the average customer balance grouped by SalesRepNo? GENERAL SALES DATABASE: SALESREP SalesRepNo RepName HireDate CUSTOMER CustNo CustName Balance SalesRepNo SELECT AVG (Balance) FROM CUSTOMER WHERE SalesRepNo; SELECT AVG (Balance) FROM CUSTOMER, SALESREP WHERE SALESREP.SalesRepNo = CUSTOMER.SalesRepNo; SELECT AVG (Balance) FROM CUSTOMER ORDER BY SalesRepNo; SELECT AVG (Balance) FROM CUSTOMER GROUP BY SalesRepNo;

SELECT AVG (Balance) FROM CUSTOMER GROUP BY SalesRepNo;

Given the following one table self-referencing relationship (primary keys underlined; foreign keys in italics):EMPLOYEE(Emp_ID, EMP_Address, EmpDateofBirth, SUPERVISOR_ID) Which statement is NOT CORRECT? Every employee must be always supervised by exactly one other employee. This is a unary self referential relationships The model can track all the supervisors an employee has had over time. birthdays can be tracked.

The model can track all the supervisors an employee has had over time.

Given the following relational model, answer the question below.EMPLOYEE (Emp_ID, EMP_Address, EmpDateofBirth, SUPERVISOR, DNR)DEPARTMENT(DNR, DName, DLocation) Which statement is NOT CORRECT? A given employee (Bob) has one department. A given department (accounting) may be the home of many employees. The primary key of department is copied to employee as a foreign key The primary key of employee is copied to department as a foreign key.

The primary key of employee is copied to department as a foreign key.

A 1:1 relationship is one of the three types of relationships in relational database design True False

True

A calculated field is considered poor design practice. True False

True

A primary key is a combination of one or more columns that is used to identify particular rows in a table. True False

True

A validation table can be used to enforce business rules. True False

True

According to Hernandez, a database's objectives represent specific tasks users wish to accomplish with the database. True False

True

An ideal field in a database usually represents a distinct characteristic of the subject of the table. True False

True

In a relationship with mandatory participation, then at least one record must exist in this table before you can enter records into the related table. True False

True

One uses the SELECT command to pull data from a table in a query. True False

True

The SQL keyword SELECT is used to specify the columns to be listed in the query results. True False

True

The SQL wildcard character "%" represents a series of one or more unspecified characters. True False

True

The rows of the result table can be sorted by the values into descending order using the DESC command. True False

True

To refer to a set of values needed for a condition, use the IN operator. True False

True

We want a query to list the names of majors with more than 50 declared students. Which term in the following SQL query is incorrect? SELECT Count(StudentID), StudentMajorFROM StudentsGROUP BY StudentMajorWHERE Count(StudentID) >50 SELECT WHERE FROM GROUP BY

WHERE

Which symbol represents an optional relationship when using an entity relationship diagram (ERD)? Choose the best answer. a vertical line a diamond a bubble a double line

a bubble

Which of the following is not a step of database design according to Hernandez: normalization requirements analysis application processing data modeling

application processing

The best solution to a multivalued field problem in relational database design is to: use a spreadsheet change the data type create a new related table spread out the values into multiple fields.

create a new related table

According to Hernandez, which of the following does NOT describe the purpose of a linking table? avoid non strategic duplicate data in tables create a M:N relationship have duplicate data in both tables ensure that each row of a table is uniquely identified

ensure that each row of a table is uniquely identified

What term best describes item Y in the entity relationship diagram shown below: linking table parent table subset table child table

linking table

Hernadez compares the _______________ design of a database to an architectural blueprint logical design thruput design analytical design physical design

logical design

many to many

many to many

Which of the following allows you to create relationships between tables in SQL? matching number of records matching PK/FK values entity integrity using the same names for the two tables

matching PK/FK values

Which of the following relation types is described below: "a single record in the first table is related to zero or one record in the second table. A single record in the second table is related to one and only one record in the first table" many to many one to many one to one

one to one

A tuple is also known as a ________. row field relation table

row

All of the following are examples of poor field designs cited by Hernadez except: sorting field multivalued field calculated field multipart field

sorting field

Maximum degree of participation refers to ________. the most instances of one entity class that can be involved in a relationship instance with another entity class whether or not an instance of one entity class is required to be related to an instance of another entity class the minimum number of entity classes involved in a relationship whether or not an entity is a weak entity

the most instances of one entity class that can be involved in a relationship instance with another entity class


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