Tokenization requires at least ____ database(s).

One database would imply storing both the sensitive data and the tokens in the same place, which defeats the security purpose of tokenization, which is to separate the sensitive data.

Tokenization usually involves separating the sensitive data from its tokenized representation. This setup typically requires at least two databases: one to store the actual sensitive data (often in a secure, segmented environment) and a separate 'token vault' database to store the tokens and their corresponding mappings to the original data, ensuring the original data is never stored with the token.

While more than two databases might be used for complex tokenization schemes, two is the minimum required for the fundamental separation of sensitive data from its tokenized representation.

Four databases are not a minimum requirement for the basic functional principle of tokenization.