http://iggyfernandez.wordpress.com/2011/11/30/the-12-days-of-sql-day-1/
PROCEDURE: cannot return a value
Function - return value
-- java hibernate not set session
create or replace trigger login_trigger
after logon on database
begin
if (USER in ('S_OST','T_SHEF')) then
execute immediate
'alter session set current_schema=' || USER;
end if;
end;
/
show error;
begin
execute immediate
'alter session set current_schema=' || USER;
end;
/