CREATE TABLE table_name_12 (samples_taken INT, melamine_content_mg_kg_ VARCHAR, producer VARCHAR)

How many samples taken from producer Qingdao Suncare Nutritional Technology with a melamine content less than 53.4?
SELECT SUM(samples_taken) FROM table_name_12 WHERE melamine_content_mg_kg_ < 53.4 AND producer = "qingdao suncare nutritional technology"
SELECT SUM("samples_taken") FROM "table_name_12" WHERE "melamine_content_mg_kg_" < 53.4 AND "producer" = "qingdao suncare nutritional technology"