Table: episodes_7
Columns: col
title
directed_by
written_by
original_air_date
production_code
u_s_viewers_millions

Question: When did the episode titled "Winterland" air for the first time? 
SQL: SELECT "original_air_date" FROM episodes_7 WHERE "title" = '"Winterland"'

Question: How many different original air dates did the episode number 6 have? 
SQL: SELECT COUNT("original_air_date") FROM episodes_7 WHERE "col" = 6

Question: Who wrote the episode with production code 1ANJ01?
SQL: SELECT "written_by" FROM episodes_7 WHERE "production_code" = '1ANJ01'