What is the following command used for?

Creating backdoors via SQL injection usually involves writing files to the server or creating new user accounts, which is a different objective than just enumerating databases.

Enumerating databases via SQL injection typically involves crafting queries that leverage system tables, such as `information_schema.schemata`, to list all available database names. This step helps attackers discover potential targets for further data exfiltration or manipulation.

Retrieving SQL statements being executed on a database typically requires direct database monitoring tools or access to logs, not a standard SQL injection payload for enumeration.

Searching database statements at an IP address is vague; SQL injection operates within the context of a web application interacting with its database, not directly searching statements at an arbitrary network address.