How to write a Query to find out if the item has been purchased in the last year

I have a table ,where I have fields like Item and Purchase date. There are multiple entries of item purchased on different dates. I want to only select those items that are NOT purchased in the last 12 months. For eg. as shown below, I just need the value of ‘IPad’ as it has never been purchased in last 12 months.

**Item*** **Purchase Date**
 Laptop      22-Mar-19
 Laptop      17-Nov-16
 Laptop      26-Jan-15
 Laptop      27-Nov-19
 Ipad        26-Jan-17
 Ipad        5-Sep-16
 Ipad        12-Jan-15

How can I achieve it using an Oracle sql query ?

Answer

With NOT EXISTS:

select distinct item
from tablename t
where not exists (
  select 1 from tablename
  where item = t.item and purchase_date > add_months(sysdate, -12)
) 

or:

select item
from tablename
group by item
having max(purchase_date) < add_months(sysdate, -12)