Using AND and OR Together
Use parentheses to group conditions correctly.
The Problem
sql
1-- Ambiguous without parentheses
2SELECT * FROM students
3WHERE course = 'Python' OR course = 'JavaScript'
4AND marks > 80;The Solution: Parentheses
sql
1-- Clear intention
2SELECT * FROM students
3WHERE (course = 'Python' OR course = 'JavaScript')
4AND marks > 80;Operator Precedence
AND is evaluated before OR. Use parentheses to be explicit.
Example
High-scoring Python or JavaScript students:
sql
1SELECT * FROM students
2WHERE (course = 'Python' OR course = 'JavaScript')
3AND marks > 80;