CREATE TABLE table_name_50 (diameter__km_ INT, latitude VARCHAR, year_named VARCHAR, longitude VARCHAR)

What is the diameter for 1997 when longitude is 212.0e and latitude is 47.0n?
SELECT MIN(diameter__km_) FROM table_name_50 WHERE year_named = 1997 AND longitude = "212.0e" AND latitude = "47.0n"
SELECT MIN("diameter__km_") FROM "table_name_50" WHERE "212.0e" = "longitude" AND "47.0n" = "latitude" AND "year_named" = 1997