Given tables employees(id, salary) and departments(min_salary), which query finds employees whose salary is less than some department's minimum salary?
hard📝 Application Q9 of 15
PostgreSQL - Subqueries in PostgreSQL
Given tables employees(id, salary) and departments(min_salary), which query finds employees whose salary is less than some department's minimum salary?
ASELECT id FROM employees WHERE salary < ALL (SELECT min_salary FROM departments);
BSELECT id FROM employees WHERE salary < ANY (SELECT min_salary FROM departments);
CSELECT id FROM employees WHERE salary > ANY (SELECT min_salary FROM departments);
DSELECT id FROM employees WHERE salary > ALL (SELECT min_salary FROM departments);
Step-by-Step Solution
Solution:
Step 1: Understand requirement
Find employees with salary less than at least one department's minimum salary.
Step 2: Use ANY keyword with < operator
salary < ANY (subquery) means salary less than some min_salary values.
Final Answer:
SELECT id FROM employees WHERE salary < ANY (SELECT min_salary FROM departments); -> Option B
Quick Check:
ANY with < means less than some values [OK]
Quick Trick:Use ANY with < to check less than some subquery values [OK]
Common Mistakes:
Using ALL instead of ANY for some condition
Using > operator instead of <
Misunderstanding ANY meaning
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