Question

I’m new to sql, and came across a little problem.
I have a query that goes like this:

select cust_id, count(1) from all_customers
group by cust_id
having count(1)>4;

that query gives me the result i want.

I need to make a new query of all the customers in all_customers table, and exclude the result I just got from the query above.
I tried doing something like this:

select * from all_customers
where cust_id NOT IN 
(
    select cust_id, count(1) from all_customers
    group by cust_id
    having count(1)>4
)

But I get the error message too many values.
What am I doing wrong?

Answer 1

You should get rid of the aggregated column in your NOT IN clause. The reason is you are only comparing cust_id column. Also note that when using NOT IN, a subquery should always return single column.

select * 
from all_customers
where cust_id NOT IN 
      (
         select cust_id 
         from all_customers
         group by cust_id
         having count(1)>4
      )