Web Exploitation SQL Injection: The Complete Guide to UNION and Error-Based Exploitation
A practical guide to UNION-based and error-based SQL injection, payload crafting with information_schema, and blue-team defenses.
sqlmap
Web Exploitation 
Web Exploitation Blind SQL Injection: Boolean-Based and Time-Based Inference Techniques
A practical guide to blind SQL injection: boolean-based and time-based inference, SUBSTRING/SLEEP payloads, and blue-team defenses.
Web Exploitation SQLMap in Practice: From Detection to OS Shell
A practical SQLMap workflow covering request files, database enumeration, data dumping, OS shells, and WAF evasion with tamper scripts.