Végső eredmény: | customer_id | gap_days | |-------------|----------| | 1 | 123 | | 2 | 120 | with cte as( select order_id, customer_id, order_dt, lag(order_dt) over(partition by customer_id order by order_dt) as prev_order_ft, datediff(day, prev_order_ft, order_dt) as gap_days from Orders ) select customer_id, max(gap_days) as gap_days from cte where gap_days > 60 group by customer_id