Introduction to SQL What operator tests column for the absence of data? NOT operator IS NULL operator None of these EXISTS operator NOT operator IS NULL operator None of these EXISTS operator ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL There is an equivalent join expression that can be substituted for all subquery expressions. False True False True ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL Which of the following query finds the name of the sailors who have reserved at least two boats? SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid ≠ r2.bid All of these SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND COUNT(r1.bid) > r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid <> r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid ≠ r2.bid All of these SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND COUNT(r1.bid) > r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid <> r2.bid ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL Find the name of those cities with temperature and condition whose condition is either sunny or cloudy but temperature must be greater than 70oF. SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' AND condition = 'cloudy' OR temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' OR condition = 'cloudy' OR temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' OR condition = 'cloudy' AND temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' AND condition = 'cloudy' AND temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' AND condition = 'cloudy' OR temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' OR condition = 'cloudy' OR temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' OR condition = 'cloudy' AND temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' AND condition = 'cloudy' AND temperature > 70; ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL Find the name of all cities with their temperature, humidity and countries. SELECT weather.city, temperature, humidity, country FROM weather, location WHERE weather.city = location.city; SELECT weather.city, temperature, humidity, country FROM weather, location; SELECT city, temperature, humidity, country FROM location; SELECT weather.city, temperature, humidity FROM weather SELECT country FROM location WHERE weather.city = location.city; SELECT weather.city, temperature, humidity, country FROM weather, location WHERE weather.city = location.city; SELECT weather.city, temperature, humidity, country FROM weather, location; SELECT city, temperature, humidity, country FROM location; SELECT weather.city, temperature, humidity FROM weather SELECT country FROM location WHERE weather.city = location.city; ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL In SQL, which command is used to change a table's storage characteristics? ALTER TABLE None of these MODIFY TABLE CHANGE TABLE ALTER TABLE None of these MODIFY TABLE CHANGE TABLE ANSWER DOWNLOAD EXAMIANS APP