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_21696800_1 (_number VARCHAR, directed_by VARCHAR)

### Question ###
How many different episode numbers are there for episodes directed by Wayne Rose?

### Accurate SQL ###

SELECT COUNT(_number) FROM table_21696800_1 WHERE directed_by = "Wayne Rose"