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 table_name_15 (notes VARCHAR, channel VARCHAR, time VARCHAR)

### Question ###
What is the notes of the transmission on channel bbc four and a time of 22:30?

### Accurate SQL ###

SELECT notes FROM table_name_15 WHERE channel = "bbc four" AND time = "22:30"