USE [BT]
	GO

	insert into T2 (k1, k2, k3)


   
    SELECT T1.k1, T1.k2, NULL FROM T1
    LEFT JOIN
    ( SELECT DISTINCT T1.k1, T1.k2 FROM T1
      JOIN T2
      ON T1.k1 = T2.k1 AND T1.k2 = T2.k2 ) wspolne
    ON T1.k1 = wspolne.k1 AND T1.k2 = wspolne.k2
    WHERE wspolne.k1 IS NULL

	go