Table: imsa_1978_race_data
Columns: race
length
class
circuit
date

Question: Which date was held at Laguna Seca Raceway, in class GTX/GTO?
SQL: SELECT "date" FROM imsa_1978_race_data WHERE "circuit" = 'laguna seca raceway' AND "class" = 'gtx/gto'

Question: Which circuit was held on May 7 for 1 hour?
SQL: SELECT "circuit" FROM imsa_1978_race_data WHERE "date" = 'may 7' AND "length" = '1 hour'

Question: Which circuit has a length of 45 minutes and is held on August 6?
SQL: SELECT "circuit" FROM imsa_1978_race_data WHERE "length" = '45 minutes' AND "date" = 'august 6'

Question: What is the length of the 6 Hours of Talladega?
SQL: SELECT "length" FROM imsa_1978_race_data WHERE "race" = '6 hours of talladega'