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create table record(
id int primary key,
category varchar(100),
item varchar(100)
);
insert into record(id,category,item) values
(1,'school','Pen'),
(2,'school','Paper'),
(3,'food','Bubble Gum'),
(4,'food','Sandwich'),
(5,'food','Pepper'),
(6,'new_food','Bubble Gum'),
(7,'new_food','Sandwich'),
(8,'new_food','Pepper');
Query was empty
select category
from ( select category,
rank() over( order by count(distinct item) desc ) as rnk
from record
group by category
) as tbl
where rnk=1;
| category |
|---|
| food |
| new_food |