I have this SELECT clause as part of a larger query: FIRST_VALUE(drs.id) OVER (PARTITION BY drs.order_ID ORDER BY drs.position ASC) AS current_drs_id Seems reasonable to me: group and sort the fields in this table and give me the first value.
But I get "column "drs.id" must appear in the GROUP BY clause or be used in an aggregate function". Huh?
