SQL Injection Prevention

SQL Injection Prevention is a SQL statement in the SELECT Queries category. SQL injection prevention: always use parameterized queries. Never trust user input concatenated into SQL. The syntax is -- Use parameterized queries/prepared statements. NEVER concatenate user input into SQL strings.. It returns security best practice. A typical example: -- VULNERABLE (NEVER DO THIS): -- SELECT * FROM users WHERE username = user_input; -- User input: anything OR 1=1; -- Result: malicious query returns all users -- SAFE: Use parameterized queries (placeholders) -- Dont concatenate user input directly into SQL -- Use: ? (MySQL), $1 (PostgreSQL), @user (SQL Server) -- PreparedStatement in application code handles escaping A close relative is SELECT, which retrieves data from a table. The most fundamental SQL statement. A close relative is SELECT *, which selects all columns from a table. A close relative is SELECT DISTINCT, which returns only distinct (unique) values from the specified columns.