Deck 6: Introduction to SQL

Question 1

What does the following SQL statement do?
Alter Table Customer_T
Add (Type Varchar (2));

A) Alters the Customer_T table to accept Type 2 Varchars
B) Alters the Customer_T table to be a Type 2 Varchar
C) Alters the Customer_T table, and adds a field called "Type"
D) Alters the Customer_T table by adding a 2-byte field called "Varchar"

Answer 1

C

Question 2

What does the following SQL statement do?
Select * From Customer Where Cust_Type = "Best"

A) Selects all the fields from the Customer table for each row with a customer labeled "best"
B) Selects the "*" field from the Customer table for each row with a customer labeled "best"
C) Selects fields with a "*" in them from the Customer table
D) Selects all the fields from the Customer table for each row with a customer labeled "*"

Answer 2

A

Question 3

________ is a set of commands used to update and query a database.

A) DML
B) DDL
C) DCL
D) DPL

Answer 3

A

Question 4

The command for creating a database is:

A) create table.
B) create view.
C) create schema.
D) create authorization.

Question 5

Which of the following is a technique for optimizing the internal performance of the relational data model?

A) Avoiding indexes on secondary keys
B) Clustering data
C) Not reporting statistics to save machine resources
D) Using random index organizations

Question 6

________ is a set of commands used to control a database,which includes security.

A) DML
B) DDL
C) DCL
D) DPL

Question 7

The benefits of a standardized relational language include:

A) application longevity.
B) reduced training costs.
C) cross-system communication.
D) all of the above.

Question 8

Which of the following questions is answered by the SQL statement?
Select Count (Product_Description)from Product_T;

A) How many products are in the Product Table?
B) How many products have product descriptions in the Product Table?
C) How many characters are in the field name "Product_Description"?
D) How many different columns named "product Description" are there in table Product_T?

Question 9

The SQL command ________ adds one or more new columns to a table.

A) create table
B) alter table
C) create view
D) create relationship

Question 10

The SQL command ________ defines a logical table from one or more tables or views.

A) create table
B) alter table
C) create view
D) create relationship

Question 11

What does the following SQL statement do?
Update Product_T
Set Unit_Price = 775
Where Product_ID = 7

A) Changes the price of a unit called Product_T to 7
B) Changes the unit price of Product 7 to 775
C) Changes the length of the Unit_Price field to 775
D) Updates the Product_T table to have a unit price of 775

Question 12

The ________ is the structure that contains descriptions of objects such as tables and views created by users.

A) SQL
B) schema
C) catalog
D) master view

Question 13

What does the following SQL statement do?
Delete from Customer_T
Where state = 'HI';

A) Deletes all records from customer_t where the state is equal to HI
B) Removes the customer_t table from the database
C) Deletes all records from the customer_t table
D) None of the above

Question 14

The first in a series of steps to follow when creating a table is to:

A) identify columns that must be unique.
B) identify each attribute and its characteristics.
C) create an index.
D) identify columns that must be null.

Question 15

Any create command may be reversed by using a ________ command.

A) truncate
B) drop
C) delete
D) unpack

Question 16

Indexes are created in most RDBMSs to:

A) provide a quicker way to store data.
B) decrease the amount of disk space utilized.
C) provide rapid random and sequential access to base-table data.
D) increase the cost of implementation.

Question 17

Which of the following is a purpose of the SQL standard?

A) To specify syntax and semantics of SQL data definition and manipulation
B) To specify minimal and complete standards, which permit different degrees of adoption in products
C) To define the data structures and basic operations for SQL databases
D) All of the above

Question 18

DDL is typically used during which phases of the development process?

A) Implementation
B) Physical design
C) Analysis
D) All of the above

Question 19

What result will the following SQL statement produce?
Select Avg(standard_price)as average from product_v;

A) The average of all products in product_v
B) The average standard_price of all products in product_v
C) The average price of all products
D) None of the above

Question 20

In an SQL statement,which of the following parts states the conditions for row selection?

A) Select
B) From
C) Where
D) Group By

Question 21

What results will be produced by the following SQL query?
Select sum(standard_price)as total_price
From product_v
Where product_type = 'WOOD';

A) The total price of all products that are of type wood
B) The total price of all products
C) The standard_price of the first wood product in the table
D) The standard_price of any wood product in the table

Question 22

What will be returned when the following SQL query is executed?
Select driver_no,count(*)as num_deliveries
From deliveries
Group by driver_no
Having count(*)> 2;

A) A listing of all drivers who made more than 2 deliveries as well as a count of the number of deliveries
B) A listing of all drivers
C) A listing of the number of deliveries greater than 2
D) A listing of all drivers who made more than 2 deliveries

Question 23

Which of the following is the wildcard operator in SQL statements?

A) < >
B) *
C) =
D) &

Question 24

To eliminate duplicate rows in a query,the ________ qualifier is used in the SQL Select command.

A) alter
B) distinct
C) check
D) specific

Question 25

What will be returned when the following SQL statement is executed?
Select driver_no,count(*)as num_deliveries
From deliveries
Group by driver_no;

A) A listing of all drivers, sorted by driver number
B) A listing of each driver as well as the number of deliveries that he or she has made
C) A count of all of the deliveries made by all drivers
D) None of the above

Question 26

To get all the customers from Hawaii sorted together,which of the following would be used?

A) Order By
B) Group By
C) Having
D) Sort

Question 27

What will result from the following SQL Select statement?
Select min(product_description)
From product_v;

A) The minimum value of product_description will be displayed.
B) An error message will be generated.
C) The first product description alphabetically in product_v will be shown.
D) None of the above.

Question 28

A single value returned from an SQL query that includes an aggregate function is called a(n):

A) agate.
B) scalar aggregate.
C) vector aggregate.
D) summation.

Question 29

Which of the following finds all groups meeting stated conditions?

A) Select
B) Where
C) Having
D) Find

Question 30

Which of the following counts ONLY rows that contain a value?

A) Count
B) Count(*)
C) Tally(*)
D) Checknum

Question 31

Which of the following can produce scalar and vector aggregates?

A) Order By
B) Group By
C) Having
D) Sort

Question 32

What will be returned when the following SQL statement is executed?
Select driver_no,count(*)as num_deliveries
From deliveries
Where state = 'MA'
Group by driver_no;

A) A listing of all drivers who made deliveries to state = 'MA', sorted by driver number
B) A listing of each driver who made deliveries to state = 'MA' as well as the number of deliveries that each driver has made to that state
C) A count of all of the deliveries made to state = 'MA' by all drivers.
D) None of the above.

Question 33

A ________ view is materialized when referenced.

A) virtual
B) dynamic
C) materialized
D) base

Question 34

What result set will the following query return?
Select item_no
From order_v
Where quantity > 10;

A) The item_no of all orders that had more than 10 items
B) The order_id of all orders that had more than one item
C) The order_id of all orders that had more than 10 items
D) The item_no of all orders that had 10 or more items

Question 35

Which of the following will produce the minimum of all standard prices?

A) Select standard_price from product_v where standard_price = min;
B) Select min(standard_price) from product_v;
C) Select standard_price from min(product_v);
D) Select min(standard_price) from product_v where standard_price = min(standard_price);

Question 36

What result set will the following query return?
Select item_no,description
From item
Where weight > 100 and weight < 200;

A) The item_no and description for all items weighing less than 100
B) The item_no for all items weighing between 101 and 199
C) The item_no and description for all items weighing between 101 and 199
D) The item_no for all items weighing more than 200

Question 37

Multiple values returned from an SQL query that includes an aggregate function are called:

A) vector aggregates.
B) scalar aggregates.
C) agates.
D) summations.

Question 38

What result set is returned from the following query?
Select customer_name,telephone
From customers
Where city in ('Boston','New York','Denver');

A) The customer_name and telephone of all customers
B) The customer_name and telephone of all customers living in either Boston, New York or Denver
C) The customer_name and telephone of all customers living in Boston and New York and Denver
D) The customer_name of all customers living in Boston, New York or Denver

Question 39

A view may not be updated directly if it contains:

A) the distinct keyword.
B) derived columns and expressions in the select clause.
C) uses the group by or having clause.
D) all of the above.

Question 40

Which of the following is true of the order in which SQL statements are evaluated?

A) The select clause is always processed first.
B) The select clause is always processed last.
C) The select clause is processed before the order by clause.
D) The group by clause is processed before the where clause.

Question 41

A major benefit of SQL as a standard is reduced training costs.

Question 42

When creating tables,it's important to decide which columns will allow null values before the table is created.

Question 43

One of the original purposes of the SQL standard was to provide a vehicle for portability of database definition and application modules between conforming DBMSs.

Question 44

The DELETE TABLE DDL command is used to remove a table from the database.

Question 45

A referential integrity constraint specifies that the existence of an attribute in one table depends upon the existence of a foreign key in the same or another table.

Question 46

Some DBMS can handle graphic data types,as well as text and numbers.

Question 47

The DROP command deletes rows from a table individually or in groups.

Question 48

SQL is both an American and international standard for database access.

Question 49

A database table is defined using the data definition language (DDL).

Question 50

SQL originated from a project called System-S.

Question 51

The ALTER TABLE command is used to change a table definition.

Question 52

DCL is used to update the database with new records.

Question 53

A database is maintained and queried using the data mapping language (DML).

Question 54

A catalog is the structure that contains object descriptions created by a user.

Question 55

Applications can be moved from one machine to another when each machine uses SQL.

Question 56

Implementation of a standard can never stifle creativity and innovation.

Question 57

When creating a table,it is not important to consider foreign key?primary key mates.

Question 58

The CREATE SCHEMA DDL command is used to create a table.

Question 59

The SQL command used to populate tables is the INSERT command.

Question 60

SQL has been implemented only in the mainframe and midrange environments.

Question 61

The ORDER BY clause sorts the final results rows in ascending or descending order.

Question 62

When a GROUP BY clause is included in an SQL statement,only those columns with a single value for each group can be included.

Question 63

The asterisk (*)wildcard designator can be used to select all fields from a table,as well as in WHERE clauses when an exact match is not possible.

Question 64

The WHERE clause is always processed before the GROUP BY clause when both occur in a SELECT statement.

Question 65

If multiple Boolean operators are used in an SQL statement,NOT is evaluated first,then AND,then OR.

Question 66

The ORDER BY clause is the first statement processed in an SQL command.

Question 67

Adding the DISTINCT keyword to a query eliminates duplicates.

Question 68

The comparison operators = and != are used to establish a range of values.

Question 69

Count(*)tallies only those rows that contain a value,while Count counts all rows.

Question 70

A single value returned from an SQL query that includes an aggregate function is called a vector aggregate.

Question 71

The following two SQL statements will produce different results.
Select last_name,first_name
from customer
where state = 'MA' or state = 'NY' or state = 'NJ' or state = 'NH' or state = 'CT';
Select last_name,first_name
from customer
where state in ('MA','NY','NJ','NH','CT');

Question 72

The WHERE clause includes the conditions for row selection within a single table or view,and the conditions between tables or views for joining.

Question 73

The following query totals sales in state= 'MA' for each salesperson.
Select salesperson_id,sum(sales)
from salesperson
group by salesperson_id
having state = 'MA';

Question 74

The HAVING clause and the WHERE clause perform the same operation.

Question 75

The following two SQL statements will produce the same results.
Select last_name,first_name
from customer
where credit_limit > 99 and credit_limit < 10001;
Select last_name,first_name
from customer
where credit_limit between 100 and 10000;

Question 76

Expressions are mathematical manipulations of data in a table that may be included as part of the SELECT statement.

Question 77

The following query totals sales for each salesperson.
Select salesperson_id,sum(sales)
from salesperson
group by salesperson_id;

Question 78

In order to update data in SQL,one must inform the DBMS which relation,columns,and rows are involved.

Question 79

The FROM clause is the first statement processed in an SQL command.

Question 80

Indexes generally slow down access speed in most RDMS.