CREATE TABLE table_name_63 (date VARCHAR2, competition VARCHAR2, result VARCHAR2)

On What Date is the Competition Semifinal that has a result of 2-1 aet?
SELECT date FROM table_name_63 WHERE competition = "semifinal" AND result = "2-1 aet"
SELECT "date" FROM "table_name_63" WHERE "2-1 aet" = "result" AND "competition" = "semifinal"