Introduction to SQL
A subquery in an SQL SELECT statement:

cannot have its results sorted using ORDER BY.
can only be used with two tables.
can always be duplicated by a join.
has a distinct form that cannot be duplicated by a join.

ANSWER DOWNLOAD EXAMIANS APP

Introduction to SQL
Which of the following query finds the total rating of the sailors who have reserved boat "103"?

SELECT SUM(s.rating) FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103
c) SELECT COUNT(s.rating) FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103
SELECT SUM(s.rating) FROM sailors s, reserves r AND r.bid = 103;
SELECT s.rating FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103

ANSWER DOWNLOAD EXAMIANS APP

Introduction to SQL
To define what columns should be displayed in an SQL SELECT statement:

use SELECT to name the source table(s) and list the columns to be shown after USING.
use FROM to name the source table(s) and list the columns to be shown after SELECT.
use USING to name the source table(s) and list the columns to be shown after WHER
use USING to name the source table(s) and list the columns to be shown after SELECT.

ANSWER DOWNLOAD EXAMIANS APP