Hello,
you have to connect the condition in the ON clause by an AND instead of a ",".
var_out = SELECT T2."PARTNER",T1."BU_GROUP",T2."MANDT",T1."CNT"
from "SAPDM1"."BUT000" AS T1
INNER JOIN
"SAPDM1"."BUT100" AS T2
ON T1."PARTNER" = T2."PARTNER"
AND T1."PARTNER_GUID" = T2."PARTNER_GUID"
AND T1."MANDT" = T2."MANDT";
Best Regards,
Florian
PS: Please check also if table BUT100 contains a field "PARTNER_GUID". If I remember correct, it just contains the MANDT and PARTNER field.