set echo off
set verify off
set serveroutput on size 100000
column fname new_value fname noprint
SELECT 'mylog_' || to_char(sysdate, 'yymmdd_sssss') ||'.log' fname FROM dual;
spool &fname
begin
  insert into T (select * from cat);
  dbms_output.put_line('===========================================');
  dbms_output.put_line('First insert: inserted '||sql%rowcount||' rows.');
  dbms_output.put_line('===========================================');
end;
/
prompt ===========================================
prompt Second insert just using SQL
prompt ===========================================
insert into T (select * from cat);
spool off

set serveroutput on
--set scan on
COLUMN XXX new_val YYY noprint
SELECT TO_CHAR (SYSDATE, 'DD-MON-YYYY HH24:MI') XXX FROM dual;
prompt The date is &YYY

SQL> -- I set scan off in my login.sql, so I'm setting it on again here
SQL> set scan on
SQL> create table emp_tst(branchname varchar2(10), name varchar2(10));

Table created.

SQL> insert into emp_tst values ('HQ', 'Charlie');

1 row created.

SQL> -- test the queries in isolation
SQL> select branchname from emp_tst where name = 'Charlie';

BRANCHNAME
----------
HQ

SQL> select branchname b_name from emp_tst where name = 'Charlie';

B_NAME
----------
HQ

SQL> -- ex1
SQL> column branchname new_val ZZZ noprint
SQL> select branchname from emp_tst where name = 'Charlie';

SQL> prompt the value is &ZZZ
the value is HQ
SQL> -- ex2
SQL> column b_name new_val ZZZ noprint
SQL> select branchname b_name from emp_tst where name = 'Charlie';

SQL> prompt the value is &ZZZ
the value is HQ