Which command allows the removal of all rows from a table but flushes a table more efficiently since no rollback information is retained?

The command that allows the removal of all rows from a table but flushes a table more efficiently since no rollback information is retained is the "TRUNCATE TABLE" command in SQL (Structured Query Language).

Here are the steps to use it:

1. Open your SQL command line client or interface.
2. Connect to the database where the table is located using your credentials.
3. Once you're connected, you can use the TRUNCATE TABLE command. The syntax is as follows: TRUNCATE TABLE table_name; Replace "table_name" with the name of your table.
4. Run the command.

Please note that this operation cannot be undone. Be sure that you want to delete all the data from the table before running this command.