To prevent malicious code from being run on a database through an API request, what specific step should be taken with all incoming user data before it is used in a database query?

To prevent malicious code from being run on a database through an API request, the specific step that should be taken with all incoming user data before it is used in a database query is to utilize parameterized queries, also known as prepared statements. A parameterized query is a method of executing a database query where the SQL code is defined first with placeholders for data, and then the actual user data is provided separately. The database system, or the database driver, receives the query structure and the data as distinct components. When a parameterized query is executed, the user-supplied data is automatically treated as literal values, never as executable code. This fundamental separation ensures that malicious characters or commands embedded within the user's input, which constitute what is known as SQL injection, cannot be interpreted by the database as part of the SQL command itself. SQL injection is a web security vulnerability that allows an attacker to interfere with the queries an application makes to its database, potentially allowing them to view, modify, or delete data they are not normally able to access, or even execute administrative operations on the database. By using parameterized queries, the database explicitly knows which parts of the incoming information are the query logic and which parts are the data, thereby neutralizing any attempt to inject malicious SQL code, as the data can only ever fill a designated placeholder value.