SQL - Computer Science

Which SQL function is used to count the number of rows in a SQL query?

• COUNT()

• NUMBER()

• SUM()

• COUNT(*)

Which of the following SQL clauses is used to DELETE tuples from a database table?

• DELETE

• REMOVE

• DROP

• CLEAR

If you don’t specify ASC or DESC after a SQL ORDER BY clause, the following is used by default

• ASC

• DESC

• There is no default value

• None of the mentioned

With SQL, how do you select all the records from a table named “Persons” where the value of the column “FirstName” ends with an “a”?

• SELECT * FROM Persons WHERE FirstName=’a’

• SELECT * FROM Persons WHERE FirstName LIKE ‘a%’

• SELECT * FROM Persons WHERE FirstName LIKE ‘%a’

• SELECT * FROM Persons WHERE FirstName=’%a%’

What does the ALTER TABLE clause do?

• The SQL ALTER TABLE clause modifies a table definition by altering, adding, or deleting table columns and/or constraints

• The SQL ALTER TABLE clause is used to insert data into database table

• THE SQL ALTER TABLE deletes data from database table

• The SQL ALTER TABLE clause is used to delete a database table

The UPDATE SQL clause can _____________

• update only one row at a time

• update more than one row at a time

• delete more than one row at a time

• delete only one row at a time

How can you change “Hansen” into “Nilsen” in the “LastName” column in the Persons table?

• UPDATE Persons SET LastName=’Hansen’ INTO LastName=’Nilsen’

• MODIFY Persons SET LastName=’Nilsen’ WHERE LastName=’Hansen’

• MODIFY Persons SET LastName=’Hansen’ INTO LastName=’Nilsen’

• UPDATE Persons SET LastName=’Nilsen’ WHERE LastName=’Hansen’

SQL query to find all the cities whose humidity is 95.

• SELECT city WHERE humidity = 95

• SELECT city FROM weather WHERE humidity = 95

• SELECT humidity = 89 FROM weather

• SELECT city FROM weather

SQL query to find the temperature in increasing order of all cities.

• SELECT city FROM weather ORDER BY temperature

• SELECT city, temperature FROM weather

• SELECT city, temperature FROM weather ORDER BY temperature

• SELECT city, temperature FROM weather ORDER BY city

Find the name of those cities with temperature and condition whose condition is either sunny or cloudy but temperature must be greater than 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