SQL Practice – All-in-One File

This repository contains a single consolidated SQL file covering all major SQL concepts, assignments, and interview-style questions.
It includes queries, triggers, joins, views, procedures, and TCL operations, all written and executed in MySQL.

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📘 Contents Included in the SQL File

✅ 1. Basic SQL Queries

• SELECT, WHERE, DISTINCT
• ORDER BY, LIMIT
• IN, BETWEEN, NOT BETWEEN
• IS NULL / IS NOT NULL

✅ 2. String Functions

• UPPER(), LOWER()
• SUBSTRING()
• CONCAT()

✅ 3. Date Functions

• NOW(), YEAR(), DATEDIFF()
• Calculating employee tenure

✅ 4. Constraints

• PRIMARY KEY, FOREIGN KEY
• UNIQUE constraints
• ALTER TABLE operations

✅ 5. Aggregate Functions

• COUNT(), SUM(), AVG(), MAX(), MIN()

✅ 6. Joins

• INNER JOIN
• LEFT JOIN
• RIGHT JOIN
• Multi-table joins

✅ 7. Views

• Simple view
• Complex view joining Employees, Departments, Salaries

✅ 8. Stored Procedures

• Parameterized procedure to fetch employee details

✅ 9. Triggers

• AFTER DELETE trigger to log deleted Orders
• Using OLD values

✅ 10. Transactions (TCL Commands)

• START TRANSACTION
• SAVEPOINT
• COMMIT
• ROLLBACK
• Bank transaction scenario

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📂 File Included in this Repository

file.

2. Open the SQL file in MySQL Workbench or any SQL editor.

3. Run each section to practice concepts or prepare for interviews.

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🎯 Purpose of This Repository

This repository demonstrates practical understanding of SQL including:

• Real-world scenarios
• Database operations
• Backend logic (procedures, triggers)
• Data integrity (TCL, constraints)

Useful for:

• Data Analyst roles
• Software Developer roles
• SQL interview preparation
• Portfolio building
• Recruiter evaluation

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📬 Contact

Feel free to connect with me on LinkedIn or GitHub for any collaboration.