SQL Queries Asked In Interview

🧠 MASTER SQL INTERVIEW PATTERN Almost all queries follow this one mental flow : SELECT → FROM → WHERE → GROUP BY → HAVING → ORDER BY → LIMIT SELECT → columns / functions (SUM, COUNT, AVG) FROM → table WHERE → row filtering (LIKE, BETWEEN, IN, =) GROUP BY → grouping HAVING → group filtering ORDER BY → sorting LIMIT → restrict rows Remember this sentence: “Smart Friends Wear Green Hats On Lunch.” S → SELECT F → FROM W → WHERE G → GROUP BY H → HAVING O → ORDER BY L → LIMIT Most interview queries are just variations of this pipeline . 🔥 PATTERN 1 — RANKING / TOP VALUES Questions: 1️⃣ Nth highest salary 2️⃣ Second highest salary 12️⃣ Top N records 16️⃣ Max salary employee Pattern ORDER BY column DESC LIMIT N Example SELECT * FROM employees ORDER BY salary DESC LIMIT 3 ; Memory trick Ranking → ORDER BY + LIMIT 🔥 PATTERN 2 — DUPLICATE DETECTION Questions: 3️⃣ duplicate names 11️⃣ duplicate records Pattern GROUP BY column HAVING COUNT(*) > 1 Example SELECT name , COUNT ( * ) FROM employees GRO