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_26539 ( "No. in series" real, "No. in season" real, "Title" text, "Directed by" text, "Written by" text, "Original air date" text, "Production code" real )

### Question ###
How many production codes have an original airdate of November 16, 1990?

### Accurate SQL ###

SELECT COUNT("Production code") FROM table_26539 WHERE "Original air date" = 'November 16, 1990'