vous pouvez utiliser union si vous avez besoin d'un résultat distinct pour les deux ou union all si vous avez également besoin d'un résultat dupliqué
SELECT CustID
, DateSubmitted
, Type
, Points
FROM `trans_summary`
WHERE CustID = '10009'
UNION
SELECT CustID
, DateSubmitted
, Type
, PointTotal
FROM `ptrans_detail`
WHERE CustID = '10009'
and DateSubmitted NOT IN
(SELECT DateSubmitted FROM
`trans_summary`
WHERE CustID = '10009')
ou union tout si besoin aussi résultat dupliqué
SELECT CustID
, DateSubmitted
, Type
, Points
FROM `trans_summary`
WHERE CustID = '10009'
UNION ALL
SELECT CustID
, DateSubmitted
, Type
, PointTotal
FROM `ptrans_detail`
WHERE CustID = '10009'
and DateSubmitted NOT IN
(SELECT DateSubmitted FROM
`trans_summary`
WHERE CustID = '10009')