Deck 6: Advanced SQL

Question 1

A type of join between three tables is called a(n):

A) ternary join.
B) self-join.
C) unnatural join.
D) pinned join.

Answer 1

A

Question 2

The following code would include:
SELECT Customer_T.CustomerID, Order_T.CustomerID,
CustomerName, OrderID
FROM Customer_T, Order_T
WHERE Customer_T.CustomerID = Order_T. CustomerID;

A) all rows of the Order_T Table regardless of matches with the Customer_T Table.
B) all rows of the Customer_T Table regardless of matches with the Order_T Table.
C) only rows that match both Customer_T and Order_T Tables.
D) only rows that don't match both Customer_T and Order_T Tables.

Answer 2

only rows that match both Customer_T and Order_T Tables.

Question 3

The most commonly used form of join operation is the:

A) outer join.
B) union join.
C) equi-join.
D) natural join.

Answer 3

D

Question 4

A join operation:

A) brings together data from two different fields.
B) causes two tables with a common domain to be combined into a single table or view.
C) causes two disparate tables to be combined into a single table or view.
D) is used to combine indexing operations.

Question 5

The following code would include:
SELECT Customer_T.CustomerID,CustomerName, OrderID
FROM Customer_T LEFT OUTER JOIN Order_T ON
Customer_T.CustomerID = Order_T.CustomerID;

A) all rows of the Order_T Table regardless of matches with the Customer_T Table.
B) all rows of the Customer_T Table regardless of matches with the Order_T Table.
C) only rows that match both Customer_T and Order_T Tables.
D) only rows that don't match both Customer_T and Order_T Tables.

Question 6

A join in which the joining condition is based on equality between values in the common columns is called a(n):

A) equi-join.
B) unilateral join.
C) natural join.
D) both A and C.

Question 7

One major advantage of the outer join is that:

A) information is easily accessible.
B) information is not lost.
C) the query is easier to write.
D) information's data type changes.

Question 8

The UNION clause is used to:

A) combine the output from multiple queries into a single result table.
B) join two tables together to form one table.
C) find all rows that do not match in two tables.
D) find all rows that are in one table, but not the other.

Question 9

A join in which rows that do not have matching values in common columns are still included in the result table is called a(n):

A) natural join.
B) equi-join.
C) outer join.
D) union join.

Question 10

A ________ is a temporary table used in the FROM clause of an SQL query.

A) correlated subquery
B) derived table
C) view table
D) trigger

Question 11

The ________ operator is used to combine the output from multiple queries into a single result table.

A) INTERSECT
B) DIVIDE
C) COLLATE
D) UNION

Question 12

All of the following are guidelines for better query design EXCEPT:

A) understand how indexes are used in query processing.
B) use a lot of self-joins.
C) write simple queries.
D) retrieve only the data that you need.

Question 13

In which of the following situations would one have to use an outer join in order to obtain the desired results?

A) A report is desired that lists all customers who placed an order.
B) A report is desired that lists all customers and the total of their orders.
C) A report is desired that lists all customers and the total of their orders during the most recent month, and includes customers who did not place an order during the month (their total will be zero).
D) There is never a situation that requires only an outer join.

Question 14

Establishing IF-THEN-ELSE logical processing within an SQL statement can be accomplished by:

A) using the if-then-else construct.
B) using the immediate if statement.
C) using the CASE key word in a statement.
D) using a subquery.

Question 15

The outer join syntax does not apply easily to a join condition of more than ________ tables.

A) two
B) three
C) four
D) five

Question 16

In order for two queries to be UNION-compatible, they must:

A) both have the same number of lines in their SQL statements.
B) both output compatible data types for each column and return the same number of rows.
C) both return at least one row.
D) both return exactly one row.

Question 17

The following code would include:
SELECT Customer_T.CustomerID,CustomerName, OrderID
FROM Customer_T RIGHT OUTER JOIN Order_T ON
Customer_T.CustomerID = Order_T.CustomerID;

A) all rows of the Order_T Table regardless of matches with the Customer_T Table.
B) all rows of the Customer_T Table regardless of matches with the Order_T Table.
C) only rows that match both Customer_T and Order_T Tables.
D) only rows that don't match both Customer_T and Order_T Tables.

Question 18

The following code is an example of a(n):
SELECT Customer_T.CustomerID, Order_T.CustomerID,
CustomerName, OrderID
FROM Customer_T, Order_T
WHERE Customer_T.CustomerID = Order_T.CustomerID;

A) equi-join.
B) subquery.
C) Full Outer JOIN.
D) Right Outer JOIN.

Question 19

An operation to join a table to itself is called a(n):

A) sufficient-join.
B) inner join.
C) outer join.
D) self-join.

Question 20

A join that is based upon equality between values in two common columns with the same name and where one duplicate column has been removed is called a(n):

A) equi-join.
B) natural join.
C) multivariate join.
D) inner join.

Question 21

________ takes a value of TRUE if a subquery returns an intermediate results table which contains one or more rows.

A) In
B) Having
C) Exists
D) Extents

Question 22

In SQL, a(n) ________ subquery is a type of subquery in which processing the inner query depends on data from the outer query.

A) correlated
B) paired
C) natural
D) inner

Question 23

SQL provides the ________ technique, which involves placing an inner query within the WHERE or HAVING clause of an outer query.

A) grouping
B) joining
C) subquery
D) union

Question 24

User-defined data types:

A) are not allowed in any DBMS.
B) are only allowed in Oracle.
C) can have defined functions and methods.
D) can be used once in a system.

Question 25

What would the following view contain for values?
Create view CustomerOrders as
Select CustID, Count(*) as TotOrders, Sum(ordertotal) as Value
From customer inner join sale on customer.customer_id = sale.customer_id;

A) A listing of all customers in the customer table
B) A listing of the customer ID as well as the total number of orders and the total amount spent by the customer
C) A listing of the customer ID as well as the total orders
D) An error message

Question 26

A procedure is:

A) stored outside the database.
B) given a reserved SQL name.
C) called by name.
D) unable to be modified.

Question 27

________ use the result of the inner query to determine the processing of the outer query.

A) Correlated subqueries
B) Outer subqueries
C) Inner subqueries
D) Subqueries

Question 28

The ________ DBA view shows information about all users of the database in Oracle.

A) DBA_USERS
B) USERS
C) DBA_VIEWS
D) DBA_INDEXES

Question 29

A type of query that is placed within a WHERE or HAVING clause of another query is called a:

A) master query.
B) subquery.
C) superquery.
D) multi-query.

Question 30

A materialized view is/are:

A) a virtual table created dynamically on request by a user.
B) an in-line query.
C) copies or replica of data based on queries.
D) always an exact copy of the source table.

Question 31

The MERGE command:

A) allows one to combine the INSERT and UPDATE operations.
B) allows one to combine the INSERT and DELETE operations.
C) joins 2 tables together.
D) is always a single table operation.

Question 32

A new set of analytical functions added in SQL:2008 is referred to as:

A) OLAF functions.
B) MOLAP functions.
C) average functions.
D) OLAP functions.

Question 33

While triggers run automatically, ________ do not and have to be called.

A) trapdoors
B) routines
C) selects
D) updates

Question 34

When a user creates a virtual table it is called a(n):

A) materialized view.
B) virtual table.
C) inline view.
D) dynamic view.

Question 35

EXISTS will take a value of ________ if the subquery returns an intermediate results table which contains one or more rows.

A) false
B) 1
C) true
D) undefined

Question 36

A named set of SQL statements that are considered when a data modification occurs are called:

A) stored procedures.
B) treatments.
C) triggers.
D) trapdoors.

Question 37

SQL-invoked routines can be:

A) part of a DDL statement.
B) functions or procedures.
C) part of a DCL statement.
D) contained within a CREATE statement.

Question 38

The following code is an example of a:
SELECT CustomerName, CustomerAddress, CustomerCity, CustomerState,
CustomerPostalCode
FROM Customer_T
WHERE Customer_T.CustomerID =
(SELECT Order_T.CustomerID
FROM Order_T
WHERE OrderID = 1008);

A) correlated subquery.
B) subquery.
C) join.
D) FULL OUTER JOIN.

Question 39

All of the following are part of the coding structure for triggers EXCEPT:

A) event.
B) condition.
C) selection.
D) action.

Question 40

All of the following are advantages of SQL-invoked routines EXCEPT:

A) flexibility.
B) efficiency.
C) sharability.
D) security.

Question 41

The following code is an example of a Subquery.
SELECT Customer_T.CustomerID, Order_T.CustomerID,
CustomerName, OrderID
FROM Customer_T, Order_T
WHERE Customer_T.CustomerID = Order_T. CustomerID;

Question 42

The following statement is an example of:
CREATE TABLE Customer_t (
CustNmbr number(11,0),
CreditLimit number(6,2),
CustStart date,
CustEnd date,
PERIOD for Custperiod(CustStart,CustEnd));

A) a materialized view.
B) an application time period table.
C) a system-versioned table.
D) a dynamic view.

Question 43

If the DBA wishes to describe all tables in the database, which data dictionary view should be accessed in Oracle?

A) DBA_TAB_PRIVS
B) DBA_TAB_COMMENTS
C) DBA_TABLE_LABEL
D) DBA_TABLES

Question 44

The following queries produce the same results.
SELECT DISTINCT Customer_Name, Customer_City
FROM Customer, Salesman
WHERE Customer.Salesman_ID = Salesman.Salesman_ID
and Salesman.Lname = 'SMITH';

SELECT Customer_Name, Customer_City
FROM Customer
WHERE Customer.Salesman_ID =
(SELECT Salesman_ID
FROM Salesman
WHERE Lname = 'SMITH');

Question 45

An SQL query that implements an outer join will return rows that do not have matching values in common columns.

Question 46

A natural join is the same as an equi-join, except that it is performed over matching columns that have been defined with the same name, and one of the duplicate columns is eliminated.

Question 47

Specifying the attribute names in the SELECT statement will make it easier to find errors in queries and also correct for problems that may occur in the base system.

Question 48

There is a special operation in SQL to join a table to itself.

Question 49

Figuring out what attributes you want in your query before you write the query will help with query writing.

Question 50

A join in which the joining condition is based on equality between values in the common column is called an equi-join.

Question 51

Joining tables or using a subquery may produce the same result.

Question 52

IF-THEN-ELSE logical processing cannot be accomplished within an SQL statement.

Question 53

One major disadvantage of the outer join is that information is easily lost.

Question 54

An equi-join is a join in which one of the duplicate columns is eliminated in the result table.

Question 55

The UNION clause is used to combine the output from multiple queries into a single result table.

Question 56

Using an outer join produces this information: rows that do not have matching values in common columns are not included in the result table.

Question 57

It is better not to have a result set identified before writing GROUP BY and HAVING clauses for a query.

Question 58

The natural join is very rarely used.

Question 59

Combining a table with itself results in a faster query.

Question 60

The joining condition of an equi-join is based upon an equality.

Question 61

Correlated subqueries are less efficient than queries that do not use nesting.

Question 62

The following query will execute without errors.
SELECT Customer.Customer_Name, Salesman.Sales_Quota
FROM Customer
WHERE Customer.Salesman_ID =
(SELECT Salesman_ID
WHERE Lname = 'SMITH');

Question 63

A dynamic query is created by the user.

Question 64

Subqueries can only be used in the WHERE clause.

Question 65

The following code is an example of a correlated subquery.
SELECT CustomerName, CustomerAddress, CustomerCity, CustomerState,
CustomerPostalCode
FROM Customer_T
WHERE Customer_T.CustomerID =
(SELECT Order_T.CustomerID
FROM Order_T
WHERE OrderID = 1008);

Question 66

The following SQL statement is an example of a correlated subquery.
SELECT First_Name, Last_Name, Total_Sales
FROM Salesman s1
WHERE Total_Sales > all
(SELECT Total_Sales FROM Salesman s2
WHERE s1.Salesman_ID != s2.Salesman_ID);

Question 67

A base table is the underlying table that is used to create views.

Question 68

Triggers have three parts: the event, the condition, and the action.

Question 69

A subquery in which processing the inner query depends on data from the outer query is called a codependent query.

Question 70

EXISTS takes a value of false if the subquery returns an intermediate result set.

Question 71

A function has only input parameters but can return multiple values.

Question 72

In order to find out what customers have not placed an order for a particular item, one might use the NOT qualifier along with the IN qualifier.

Question 73

A correlated subquery is executed once for each iteration through the outer loop.

Question 74

A routine is a named set of SQL statements that are considered when a data modification occurs.

Question 75

A materialized view is not persistent.

Question 76

When a subquery is used in the FROM clause, it is called a denied table.

Question 77

When EXISTS or NOT EXISTS is used in a subquery, the select list of the subquery will usually just select all columns as a placeholder because it doesn't matter which columns are returned.

Question 78

The advantages of SQL-invoked routines are flexibility, efficiency, sharability, and applicability.

Question 79

Constraints are a special case of triggers.

Question 80

Triggers can be used to ensure referential integrity, enforce business rules, create audit trails, and replicate tables, but cannot call other triggers.