set hive.optimize.ppd=true; set hive.ppd.remove.duplicatefilters=true; create table t1 (id int, key string, value string); create table t2 (id int, key string, value string); create table t3 (id int, key string, value string); create table t4 (id int, key string, value string); explain select * from t1 full outer join t2 on t1.id=t2.id join t3 on t2.id=t3.id where t3.id=20; explain select * from t1 join t2 on (t1.id=t2.id) left outer join t3 on (t2.id=t3.id) where t2.id=20; explain select * from t1 join t2 on (t1.id=t2.id) left outer join t3 on (t1.id=t3.id) where t2.id=20; drop table t1; drop table t2; drop table t3; drop table t4;