What's the production code of the episode originally aired on February 21, 1985?
CREATE TABLE table_2818164_2 (production_code INTEGER, original_air_date VARCHAR)
SELECT MIN(production_code) FROM table_2818164_2 WHERE original_air_date = "February 21, 1985"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_2818164_2 (production_code INTEGER, original_air_date VARCHAR) Question: What's the production code of the episode originally aired on February 21, 1985? [/INST] SELECT MIN(production_code) FROM table_2818164_2 WHERE original_air_date = "February 21, 1985" </s>