Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE rooms (roomid VARCHAR, room VARCHAR)
TABLE: CREATE TABLE reservations (roomid VARCHAR, room VARCHAR)

### Question ###
Find the number of rooms that do not have any reservation.

### Accurate SQL ###

SELECT COUNT(*) FROM rooms WHERE NOT roomid IN (SELECT DISTINCT room FROM reservations)