SQL remains one of the most essential skills in software development. Nearly every application that stores and retrieves data relies on a relational database, and SQL is the language that bridges the gap between application logic and persistent storage.
From web and mobile backends to data analytics and enterprise systems, the ability to write efficient queries is a fundamental requirement for developers, data analysts, and database administrators alike.
About the book
SQL Notes for Professionals is a practical reference compiled from Stack Overflow documentation, organized into 62 concise chapters that cover the breadth of SQL. The book assumes no prior SQL knowledge and walks through everything from basic SELECT statements to advanced topics like window functions, common table expressions, and query optimization.
Each chapter focuses on a specific concept or feature, with code examples drawn from real-world scenarios. This structure makes it equally useful as a learning guide for beginners and as a quick reference for experienced developers who need to look up syntax or techniques.
What you will learn
How to write SELECT queries, filter and sort results, join tables using inner and outer joins, aggregate data with GROUP BY, use subqueries and common table expressions, create and modify database tables, work with indexes, transactions, views, stored procedures, and triggers. The book also covers security topics like SQL injection prevention and clean code practices for writing maintainable SQL.
Table of contents
- Getting started with SQL
- Identifier
- Data Types
- NULL
- Example Databases and Tables
- SELECT
- GROUP BY
- ORDER BY
- AND & OR Operators
- CASE
- LIKE operator
- IN clause
- Filter results using WHERE and HAVING
- SKIP TAKE (Pagination)
- EXCEPT
- EXPLAIN and DESCRIBE
- EXISTS CLAUSE
- JOIN
- UPDATE
- CREATE Database
- CREATE TABLE
- CREATE FUNCTION
- TRY/CATCH
- UNION / UNION ALL
- ALTER TABLE
- INSERT
- MERGE
- cross apply, outer apply
- DELETE
- TRUNCATE
- DROP Table
- DROP or DELETE Database
- Cascading Delete
- GRANT and REVOKE
- XML
- Primary Keys
- Indexes
- Row number
- SQL Group By vs Distinct
- Finding Duplicates on a Column Subset with Detail
- String Functions
- Functions (Aggregate)
- Functions (Scalar/Single Row)
- Functions (Analytic)
- Window Functions
- Common Table Expressions
- Views
- Materialized Views
- Comments
- Foreign Keys
- Sequence
- Subqueries
- Execution blocks
- Stored Procedures
- Triggers
- Transactions
- Table Design
- Synonyms
- Information Schema
- Order of Execution
- Clean Code in SQL
- SQL Injection
Book details
- Title: SQL Notes for Professionals
- Author(s): Stack Overflow
- Publication year: 2018
- Publisher: GoalKicker.com
- Pages: 166
- PDF size: 1.5 MB
- Estimated reading time: ~4 h 9 min
- Level: Beginner to Intermediate
- Main category: Databases
- Subcategory: SQL
- Language: English
- License: CC BY-SA 3.0
Legal notice: This book is shared for educational purposes only. The content is distributed under Creative Commons licenses or with explicit permission from the author. FreeProgrammingBooks may host files that comply with their respective licenses.