SQL | Data Analytics

3 Free Services for Practicing SQL 🚀 Want to improve your SQL skills without spending a dime? Here are three free platforms where you can practice and enhance your database management abilities: 1️⃣ SQLZoo Perfect for beginners! Interactive SQL lessons where you can write queries directly in the browser and get instant feedback. Whether you’re just starting or refreshing your knowledge, SQLZoo is a great place to practice. 🔗 sqlzoo.net 2️⃣ LeetCode Known for coding challenges, but its "Database" section is packed with SQL problems. From easy to hard levels, it's perfect for preparing for interviews or solving real-world database tasks. 🔗 leetcode.com 3️⃣ Mode Analytics Want to practice SQL on real data? Mode Analytics offers a smooth interface and tons of examples, helping you hone your SQL skills in data analysis and reporting. 🔗 mode.com/sql-tutorial These platforms are free and will help you level up your #SQL game! 💻🔥

#SQL commands

🔥 Key SQL Functions: A Quick Guide 🔥 If you're working with databases, knowing SQL functions is essential for writing efficient queries. Here are the main functions you should know: 1. `SELECT` – Retrieves data from a database. You can choose specific columns or use * to select all columns.

   SELECT name, age FROM users;
   

2. `WHERE` – Filters data based on specific conditions.

   SELECT * FROM users WHERE age > 30;
   

3. `JOIN` – Combines rows from two or more tables based on related columns. - `INNER JOIN` – Returns only matching records.

     SELECT * FROM orders INNER JOIN customers ON orders.customer_id = customers.id;
     

- `LEFT JOIN` – Returns all records from the left table and matching ones from the right.

     SELECT * FROM orders LEFT JOIN customers ON orders.customer_id = customers.id;
     

4. `GROUP BY` – Groups rows with the same values in specific columns.

   SELECT department, COUNT(*) FROM employees GROUP BY department;
   

5. `ORDER BY` – Sorts the result set in ascending (`ASC`) or descending (`DESC`) order.

   SELECT * FROM users ORDER BY age DESC;
   

6. `HAVING` – Filters groups after GROUP BY.

   SELECT department, COUNT(*) FROM employees GROUP BY department HAVING COUNT(*) > 5;
   

7. `LIMIT` – Restricts the number of rows returned.

   SELECT * FROM users LIMIT 10;
   

#sql_basic

Basic SQL commands #sql_basic