você pode usar o cursor ref, mas eu não o recomendaria.
create table tab_01 as select 1 a , 10 b from dual;
create table tab_02 as select 2 a , 20 b from dual;
create table tab_03 as select 3 a , 30 b from dual;
create or replace function get_all_history
return sys_refcursor
as
r sys_refcursor;
stmt varchar2(32000);
cursor c_tables is
select table_name
from user_tables
where table_name like 'TAB_%';
begin
for x in c_tables loop
stmt := stmt || ' select * from ' || x.table_name ||' union all';
end loop;
stmt := substr(stmt , 1 , length(stmt) - length('union all'));
open r for stmt;
return r;
end;
/
SQL> select get_all_history() from dual;
GET_ALL_HISTORY()
--------------------
CURSOR STATEMENT : 1
CURSOR STATEMENT : 1
A B
---------- ----------
1 10
2 20
3 30
