updated test results

max(b)

1

drop table if exists t,t1,t2;

drop table if exists t1, t2, t3, t4, t5, t6;

create table t1 (a int not null);

create table t2 (a int not null);

insert into t1 values (1);

insert into t2 values (2);

create temporary table t3 (a int not null) TYPE=MERGE UNION=(t1,t2);

select * from t3;

a

1

2

create temporary table t4 (a int not null);

create temporary table t5 (a int not null);

insert into t4 values (1);

insert into t5 values (2);

create temporary table t6 (a int not null) TYPE=MERGE UNION=(t4,t5);

select * from t6;

a

1

2

drop table if exists t1, t2, t3, t4, t5, t6;