Table number
contains many numbers in column num including duplicated ones.
Can you write a SQL query to find the biggest number, which only appears once.
+---+ |num| +---+ | 8 | | 8 | | 3 | | 3 | | 1 | | 4 | | 5 | | 6 |
For the sample data above, your query should return the following result:
+---+ |num| +---+ | 6 |
Note:
If there is no such number, just output null.
create table number (num int)
insert into number values(8)
insert into number values(8)
insert into number values(3)
insert into number values(3)
insert into number values(1)
insert into number values(4)
insert into number values(5)
insert into number values(6)
+---+
|num|
+---+
| 8 |
| 8 |
| 3 |
| 3 |
| 1 |
| 4 |
| 5 |
| 6 |
select * from number
with cte as(
select num from number
group by num
having count(num)=1
)select max(num) as Num from cte