select nitemcode from (
select * from 
(
select concat(group_code,item_code) nitemcode from itemmaster where company_id=1 and group_code not in ('999')
) a
left join
(
select concat(group_code,item_code) eitemcode from itemmaster where company_id=2 and group_code not in ('999')
) b on a.nitemcode=b.eitemcode 
) g where eitemcode is nullupdate itemmaster set threshold =1 where concat(group_code,item_code)='2071861'<br />
<b>Fatal error</b>:  Uncaught mysqli_sql_exception: UPDATE command denied to user 'tarun'@'13.126.47.172' for table 'itemmaster' in C:\xampp\htdocs\VOWDATA1xxxx\itmsep.php:30
Stack trace:
#0 C:\xampp\htdocs\VOWDATA1xxxx\itmsep.php(30): mysqli_query(Object(mysqli), 'update itemmast...')
#1 {main}
  thrown in <b>C:\xampp\htdocs\VOWDATA1xxxx\itmsep.php</b> on line <b>30</b><br />