Deck 5: Multiple-Table Queries

Question 1

In a full outer join, all rows from both tables will be included regardless of whether they match rows from the other table.

Answer 1

True

Question 2

There are three types of inner joins.

Answer 2

False

Question 3

In small databases, there is a significant time difference between different query approaches.

Answer 3

False

Question 4

You must use a comma or a period to separate a table name from its alias.

Question 5

You can perform special operations within SQL.

Question 6

It is permissible to qualify all column names in a query.

Question 7

You can join three tables together but not four tables.

Question 8

The product operation is commonly used.

Question 9

MySQL supports the INTERSECT operator.

Question 10

One reason for using an alias is simplicity.

Question 11

To ensure that query results are listed in a desired order, use the ORDER BY clause.

Question 12

When joining tables, it is always necessary to qualify a column name.

Question 13

There is only one approach to joining tables.

Question 14

You can use the ALL and ANY operators with subqueries to produce a single column of numbers.

Question 15

Occasionally, a self-join might involve the primary key of a table.

Question 16

It is easy to create a product inadvertently by omitting the WHERE clause when you are attempting to join tables.

Question 17

When using a DBMS without an optimizer, the formulation of a query can make a difference in the speed with which the query is executed..

Question 18

MySQL does not support the MINUS operator.

Question 19

You can join tables by using a condition in the WHERE clause.

Question 20

For two tables to be union compatible, the columns of the two tables must be identical.

Question 21

The ____ of two tables is the set of all rows that are in the first table but that are not in the second table.

A)union
B)intersect
C)intersection
D)difference

Question 22

You can join tables by using a condition in the ____ clause.

A)FROM
B)WHERE
C)SELECT
D)JOIN

Question 23

You must join tables on matching columns.

Question 24

You can precede a subquery with the ____ operator to create a condition that is true if one or more rows are obtained when the subquery is executed.

A)IS NULL
B)IS TRUE
C)IS EXIST
D)EXISTS

Question 25

When a subquery involves a table listed in the outer query, the subquery is called a(n)____ subquery.

A)inner outer
B)correlated
C)reverse
D)parameter

Question 26

One reason for using an alias is when you are joining a table to itself.

Question 27

The ____ of two tables is a table containing all rows that are in both tables.

A)intersect
B)union
C)difference
D)minus

Question 28

A(n)____ clause can include statistics calculated for only the groups or columns whose values are identical for each row in a group.

A)SELECT
B)WHERE
C)FROM
D)EXISTS

Question 29

To produce the same results as the INTERSECT operator, use the BETWEEN operator and a subquery.

Question 30

To qualify a column name, precede the name of the column with the name of the table, followed by a(n)____.

A),
B).
C)%
D)*

Question 31

To retrieve data from multiple tables in a query you can use the ____ operator with a subquery.

A)AND
B)IN
C)OR
D)NOT

Question 32

You can use MySQL to create a nested subquery.

Question 33

You can use the EXISTS operator to retrieve data from more than one table.

Question 34

You create an alias by typing the name of the table, pressing the ____, and then typing the name of the alias.

A)Tab
B)Backspace
C)Enter
D)Spacebar

Question 35

To produce the same results as the MINUS operator, use NOT, the IN operator and a subquery.

Question 36

To relate two tables, in the FROM clause list all columns involved in the query.

Question 37

In a nested query, the outer query is evaluated first.

Question 38

The ____ of two tables is a table containing every row that is in either the first table, the second table, or both tables.

A)intersection
B)union
C)minus
D)difference

Question 39

Table A has 10 rows and table B has 10 rows. The product of Table A and Table B would have 100 rows.

Question 40

When the innermost subquery is evaluated, a permanent table is produced.

Question 41

When tables are listed in the FROM clause, you can give each table a(n)____________________, or an alternate name.

Question 42

In a ____, all rows from the table on the left (the table listed first in the query)will be included regardless of whether they match rows from the table on the right (the table listed second in the query).

A)left inner join
B)left outer join
C)right inner join
D)right outer join

Question 43

You join tables in SQL by including a condition in the ____________________ clause to ensure that matching columns contain equal values.

Question 44

In a ____, all rows from the table on the right will be included regardless of whether they match rows from the table on the left.

A)left inner join
B)left outer join
C)right outer join
D)right inner join

Question 45

Which of the following joins compares the tables in the FROM clause and lists only those rows that satisfy the condition in the WHERE clause?

A)inner
B)outer
C)nested
D)product

Question 46

The product of two tables is formally called the ____ Product.

A)Oracle
B)Outer
C)SQL
D)Cartesian

Question 47

When there is potential ambiguity in listing column names, you must ____________________ the columns involved in the query.

Question 48

A subquery within a subquery is called a(n)____________________ subquery.

Question 49

If you precede the subquery by the ____ operator, the condition is true only if it satisfies all values produced by the subquery.

A)TRUE
B)ALL
C)IS ALL
D)ALWAYS

Question 50

In a(n)____ join, all rows from both tables are included regardless of whether they match rows from the other table..

A)normal
B)inner
C)full outer
D)combined

Question 51

If you precede the subquery by the ____ operator, the condition is true only if it satisfies any value (one or more)produced by the subquery.

A)IS SOME
B)IS ANY
C)SOME
D)ANY

Question 52

Two tables are ____ compatible if they have the same number of columns and if their corresponding columns have identical data types and lengths.

A)union
B)minus
C)difference
D)intersect

Question 53

The subquery that involves a table listed in the outer query is called a(n)____________________ subquery.

Question 54

If you had two separate tables for customers and the query requested customers in the first table having the same city as customers in the second table, you could use a normal ____________________ operation to find the answer.

Question 55

Joining a table to itself, is called a(n)____________________.

Question 56

In a multiple-table query, you list all the desired columns in the ____________________ clause and qualify any columns that appear in more than one table.

Question 57

MySQL performs many built-in ____________________ that analyze queries to determine the best way to satisfy them.

Question 58

Which of the following set operators are not supported by MySQL?

A)UNION and MINUS
B)MINUS and INTERSECT
C)UNION and INTERSECT
D)UNION and ALL

Question 59

For an SQL implementation to truly support the union operation, it must remove____ rows automatically..

A)dependent
B)no
C)independent
D)duplicate

Question 60

To retrieve data from more than one table, you must ____________________ the tables together by finding rows in the two tables that have identical values in matching columns.

Question 61

The ____________________ of two tables is the set of all rows that are in the first table but that are not in the second table.

Question 62

Why do you use the ANY and ALL operators? What is the difference between the two operators?

Question 63

A join that compares the tables in the FROM clause and lists only those rows that satisfy the condition in the WHERE clause is called a(n)____________________ join.

Question 64

Two tables are ____________________ compatible if they have the same number of columns and if their corresponding columns have identical data types and lengths.

Question 65

The ____________________ of two tables is a table containing all rows that are in both tables.

Question 66

Sometimes you need to list all the rows from one of the tables in a join, regardless of whether they match any rows in the other table. This type of join is called a(n)____________________ join.

Question 67

The ____________________ of two tables is the combination of all rows in the first table and all rows in the second table.

Question 68

What steps should you take to join (relate)tables?

Question 69

If you precede a subquery by the ____________________ operator, the condition is true only if it satisfies one or more values produced by the subquery.

Question 70

What steps should you do to construct a detailed query in a step-by-step fashion?

Question 71

Describe the types of outer joins.

Question 72

If the SQL implementation truly supports the union operation, it will remove any duplicate ____________________ automatically.

Question 73

The ____________________ of two tables is a table containing every row that is in either the first table, the second table, or both tables.

Question 74

There are three set operations: union, intersection, difference. Define each of these operations. Which one(s)does MySQL support?

Question 75

If you precede a subquery by the ____________________ operator, the condition is true only if it satisfies all values produced by the subquery.