SQL injection, or SQLi, is an attack on an SQL database where a code or database query is inserted via some form of input from a client to the application. SQLi is one of the oldest vulnerabilities, but still one of the most common and, since SQL-based databases are so common, one of the most dangerous.
The severity of SQL injection attacks is limited by the attacker's skill and imagination, and to a lesser extent, defense in depth countermeasures, such as low-privilege connections to the database server. In general, consider SQL injection a high-impact severity.
Before we can inject SQL, we should have a basic understanding of SQL and also understand database structures.
SQL is considered a fourth-generation programming language because it uses standard human-understandable words for its syntax: just English and brackets. SQL is used for databases and we can...