>>select cast(val(substr(sponsor_id,5,2)) as int) as sponsor_id, ; >> sum(amount) as amount ; >> from tip ; >> inner join ledger on ledger.tip_id = tip.tip_id and source="RTA" ; >> group by 1 >>>>This also works
>>select tip.tip_id, ; >> sum(amount) as amount ; >> from tip ; >> inner join ledger on ledger.tip_id = tip.tip_id and source="RTA" ; >> group by 1>>but this does not.
>>select tip.tip_id, cast(val(substr(sponsor_id,5,2)) as int) as sponsor_id,; >> sum(amount) as amount ; >> from tip ; >> inner join ledger on ledger.tip_id = tip.tip_id and source="RTA" ; >> group by 1>>From this I conclude that when using a Group By there can be only 2 fields in the result, the field which is being aggregated and the field that provides the "rollup". Would that be a correct conclusion?