Introduction to SQL COUNT(field_name) tallies only those rows that contain a value; it ignores all null values. True False True False 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? All of these 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 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 All of these 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 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' 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' AND 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' 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' AND temperature > 70; SELECT city, temperature, condition FROM weather WHERE condition = 'sunny' OR condition = 'cloudy' OR temperature > 70; 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 DISTINCT and its counterpart, ALL, can be used more than once in a SELECT statement. True False True False ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL The command to eliminate a table from a database is: REMOVE TABLE CUSTOMER; DELETE TABLE CUSTOMER; UPDATE TABLE CUSTOMER; DROP TABLE CUSTOMER; REMOVE TABLE CUSTOMER; DELETE TABLE CUSTOMER; UPDATE TABLE CUSTOMER; DROP TABLE CUSTOMER; ANSWER DOWNLOAD EXAMIANS APP