Practical SQL Query Examples

Practical SQL Query Examples

Given this Students table:

StudentID	Name	Age	City	Score
1	Alice	15	London	85
2	Bob	17	Manchester	72
3	Charlie	16	London	91
4	Diana	17	Leeds	68
5	Eve	15	London	95

Query 1: All London students

SELECT Name, Age FROM Students WHERE City = "London"
-- Returns: Alice (15), Charlie (16), Eve (15)

Query 2: Students aged 16+ sorted by score (highest first)

SELECT Name, Score FROM Students
WHERE Age >= 16
ORDER BY Score DESC
-- Returns: Charlie (91), Bob (72), Diana (68)

Query 3: London students with score over 90

SELECT * FROM Students
WHERE City = "London" AND Score > 90
-- Returns: Charlie (91), Eve (95)

Query 4: Students from London OR Manchester

SELECT Name, City FROM Students
WHERE City = "London" OR City = "Manchester"
-- Returns: Alice, Bob, Charlie, Eve