user: Question: How many episode air dates are there for auditioning city Rio de Janeiro?
Columns: ['Episode Air Date', 'Audition City', 'Audition Date', 'Audition Venue', 'Guest Fourth Judge']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['June 10, 2010', 'Florianópolis', 'April 10, 2010', 'Nego Quirido Sambadrome', 'Luiza Possi']
SQL:

assistant: SELECT COUNT("Episode Air Date") FROM "Table" WHERE "Audition City" = 'Rio de Janeiro';