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_45 ( episode VARCHAR, air_date VARCHAR, viewers VARCHAR )

### Question ###
What is the episode name that aired on July 23, 2009 with more than 3.31 viewers?

### Accurate SQL ###

SELECT episode FROM table_name_45 WHERE air_date = "july 23, 2009" AND viewers > 3.31