CREATE TABLE country (Country_id VARCHAR2, Country_name VARCHAR2)
CREATE TABLE match_season (Player VARCHAR2, Country VARCHAR2)

Which players are from Indonesia?
SELECT T2.Player FROM country AS T1 JOIN match_season AS T2 ON T1.Country_id = T2.Country WHERE T1.Country_name = "Indonesia"
SELECT "T2"."Player" FROM "country" "T1" JOIN "match_season" "T2" ON "T1"."Country_id" = "T2"."Country" WHERE "Indonesia" = "T1"."Country_name"