Category: MySQL Tutorial

💬 MySQL Comments In MySQL, comments are used to explain SQL code, disable statements temporarily, and improve readability.They are ignored by the MySQL engine during execution. 1️⃣ Why Use Comments? ✔ Make SQL easier...

🚫 MySQL NULL Functions – Complete Tutorial (Beginner → Interview Level) In MySQL, NULL represents missing or unknown data.MySQL provides special NULL-handling functions to test, replace, and safely work with NULL values in queries....

🧠 MySQL CASE Statement The CASE statement in MySQL is used to apply conditional logic inside SQL queries—similar to if–else in programming. 👉 It helps you return different values based on conditions. 1️⃣ What...

📥 MySQL INSERT INTO SELECT Statement The INSERT INTO SELECT statement in MySQL is used to copy data from one table to another in a single SQL query. 👉 Very useful for data migration,...

MySQL EXISTS Operator The EXISTS operator in MySQL is use to check whether a subquery returns any rows.It is often used in correlated subqueries to test the existence of related data. ✅ Returns TRUE...

🎯 MySQL HAVING Clause The HAVING clause in MySQL is used to filter grouped results produced by GROUP BY.👉 Think of HAVING as WHERE for aggregate functions. 1️⃣ What is HAVING Clause? Filters groups,...

📊 MySQL GROUP BY Statement The GROUP BY statement in MySQL is used to group rows that have the same values in specified columns and apply aggregate functions to each group. 👉 It is...

🔗 MySQL UNION ALL Operator The UNION ALL operator in MySQL is used to combine the result sets of two or more SELECT queries and include all rows, even duplicates. 👉 Think of it...