To solve this question, the user needs to know the syntax of the SELECT statement and the purpose of the DISTINCT keyword. The user must retrieve unique combinations of the POSITION and MANAGER values from the EMPLOYEE table.
Option A is the correct answer:
A. SELECT DISTINCT position, manager FROM employee;
This option retrieves unique combinations of the POSITION and MANAGER values from the EMPLOYEE table. The DISTINCT keyword ensures that each combination is unique and not repeated in the result set.
Option B is incorrect:
B. SELECT position, manager DISTINCT FROM employee;
This option is not valid because the keyword DISTINCT is in the wrong position. The correct syntax is SELECT DISTINCT, not SELECT column1, column2 DISTINCT.
Option C is incorrect:
C. SELECT position, manager FROM employee;
This option retrieves all combinations of the POSITION and MANAGER values from the EMPLOYEE table, including duplicates.
Option D is incorrect:
D. SELECT position, DISTINCT manager FROM employee;
This option is not valid because the keyword DISTINCT is in the wrong position. The correct syntax is SELECT DISTINCT, not SELECT column1, DISTINCT column2.
The Answer is: A