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_76 ( circuit VARCHAR, fastest_lap VARCHAR, date VARCHAR )

### Question ###
What circut has an unknown fastest lap on July 19?

### Accurate SQL ###

SELECT circuit FROM table_name_76 WHERE fastest_lap = "unknown" AND date = "july 19"