I saw something missing in the query.
Try this:
SELECT T1."DocNum", T0."DocNum", T1."U_L_02"
FROM ORDR T0 INNER JOIN OPOR T1 ON T0.U_L_02 = T1.U_L_02
I saw something missing in the query.
Try this:
SELECT T1."DocNum", T0."DocNum", T1."U_L_02"
FROM ORDR T0 INNER JOIN OPOR T1 ON T0.U_L_02 = T1.U_L_02