SQL INTERVIEW PREP: 20 CORE TOPICS YOU MUST MASTER BEFORE ANY DATA JOB INTERVIEW
If you want a job in Data Analysis, Data Science, or Business Intelligence, SQL is not optional — it is essential.
Most interviews don’t test memorization…
They test your understanding of core SQL concepts.
Here are 20 important SQL topics you must master:
🔹 SQL Basics & Introduction
🔹 Data Types in SQL
🔹 Database Structure (Tables, Rows, Columns)
🔹 Primary Key & Foreign Key Concepts
🔹 Constraints (NOT NULL, UNIQUE, CHECK, DEFAULT)
🔹 Filtering Data (WHERE clause)
🔹 Sorting Data (ORDER BY)
🔹 Aggregation Functions (SUM, COUNT, AVG, MIN, MAX)
🔹 GROUP BY Concept
🔹 HAVING Clause
🔹 Joins (INNER, LEFT, RIGHT, FULL OUTER)
🔹 Subqueries (Nested Queries)
🔹 Set Operations (UNION, UNION ALL, INTERSECT)
🔹 Case Statements (Conditional Logic)
🔹 NULL Handling (IS NULL / IS NOT NULL)
🔹 Views in SQL
🔹 Indexing Basics
🔹 Stored Procedures & Functions
🔹 Data Modification (INSERT, UPDATE, DELETE)
🔹 Difference Between DELETE, TRUNCATE, DROP
💡 REAL TALK:
If you understand these topics deeply, SQL interviews become 10x easier — because everything is built from them.
⚡ PRO TIP:
Don’t just read these topics.
Write queries. Build mini projects. Practice with real datasets.
Master these, and you’re already ahead in the data job market.
— Fatolu Peter
Data Analyst | Helping You Build Job-Ready Data Skills
#SQL #DataAnalytics #InterviewPrep #DataScience #BusinessIntelligence #LearnData