CREATE TABLE table_name_20 (platelet_count VARCHAR, partial_thromboplastin_time VARCHAR)

Which Platelet count has a Partial thromboplastin time of prolonged or unaffected?
SELECT platelet_count FROM table_name_20 WHERE partial_thromboplastin_time = "prolonged or unaffected"
SELECT "platelet_count" FROM "table_name_20" WHERE "partial_thromboplastin_time" = "prolonged or unaffected"