Is it possible to use a column in SELECT if we do not group by it in GROUP BY?

In SQL, if GROUP BY is used, then in the SELECT list you can specify:

• Columns that are used for grouping (in GROUP BY), or
• Aggregate functions (e.g., SUM(), COUNT(), MAX(), etc.)

If you specify a column in SELECT that is not part of the GROUP BY and not wrapped in an aggregate function, most DBMSs will produce an error because it is unclear which value of this column should be chosen from the group.

Exceptions may exist in some DBMSs with extensions (for example, MySQL in default mode), where a random value from the group is returned, but this is not recommended and can lead to incorrect results.

Therefore, the answer is: No, you cannot use a column in SELECT without grouping by it or using an aggregate function.