請把下面的HQL語句改為其他方式實現

　　1)請優化： select a.key,a.value from a where a.key not in (select b.key from b)

　　2)已優化： select t1.key,t1.value from ( select a.key,a.value from a ) t1 right join ( select b.key from b ) t2 on t1.key = t2 .key where t1.key is null;

　　3)請優化： select a.key,a.value from a where a.key in (select b.key from b)

　　4)已優化： select t1.key,t1.value from ( select a.key,a.value from a ) t1 join ( select b.key from b ) t2 on t1.key = t2 .key;

聲明：本站稿件版權均屬千鋒教育所有，未經許可不得擅自轉載。