SQL CREATE TABLE, ALTER TABLE and DROP TABLE Explained

Understand SQL DDL commands CREATE TABLE, ALTER TABLE and DROP TABLE with safe beginner examples.

DDL changes database structure. CREATE makes a table, ALTER adds or changes a column, and DROP removes the table. Practice in a test database before changing production objects.

Example

SELECT department, COUNT(*) AS student_count
FROM students
WHERE active = 1
GROUP BY department
ORDER BY student_count DESC;

Try it yourself

1. Create a small table with five rows.
2. Run the example and change one clause.
3. Explain the result in your own words.

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