group by first character

Question

I have a problem with a query in Oracle SQL.

I have a first_name column in an employees table. I want to group my records according to the

Answer 1

You'll need to group by everything that is not an aggregate function, so you can't have employee_id in the SELECT projection. You also need to group by just the first character of the first_name. Something like this should work:

SELECT  SUBSTR(first_name, 1, 1) AS alpha, COUNT(*) AS employee_count
FROM    employees
GROUP   BY SUBSTR(first_name, 1, 1);

That would group by the first letter of the first name, and show the number of employees that fall into that group.