In this case it isn't. It's better when you need a lookup to multiple columns but will not be needed in any other query/ETL job. Might be steps in a funnel or

In this case it isn't. It's better when you need a lookup to multiple columns but will not be needed in any other query/ETL job. Might be steps in a funnel or values in a bespoke customer discount query. Some DBs do allow struct/array fields but joining against a constant CTE is portable and has low overhead.