List constraints on a table

set verify off
set echo off
set pagesize 200
set linesize 150

column type format a10 heading "Type"
column cons_name format a30 heading "Name"
column status heading "Status"
column last_change heading "Last Chg"

accept tableName prompt "Table: "

select  decode(constraint_type,
                'C', 'Check',
                'O', 'R/O View',
                'P', 'Primary',
                'R', 'Foreign',
                'U', 'Unique',
                'V', 'Check view') type,
        constraint_name cons_name,
        status,
        last_change
from dba_constraints
where table_name = upper('&tableName')
order by 1
/