TABLES.
ADR6 = ADDRESS NUMBER
LFA1 = VENDOR
WYT3 = PARTNER FUNCTION TABLE
select adr6-addrnumber (email)
from table adr6 join table lfa1 with key adr6-addrnumber = lfa1-adrnr
ABAP Version :
data : lv_email like adr6-addrnumber.
select addrnumber into lv_email
from adr6 as a inner join kna1 as b on a~addrnumber = b~adrnr.