Diff between inner join and outer join_SAP刘梦_新浪博客

To keep it simple, let me keep it this way: Considering two table A and B and internal table ITAB: Inner Join: It requires an entry with KEY of A in B, to be extracted to internal table. Outer Join: Irrespective of whether an entry exists or not in B it still extracts data from A. Eg:

Table: A

--------

Fld1 Fld2

------------

X 100

Y 200

Z 300

Table: B

--------

Fld1 Fld3

------------

X abc

X def

Z pqr " No entry for Key Y in table B so it is not extracted

ITAB fields: FLD1, FLD2, FLD3

Inner Join:

-----------

FLD1 FLD2 FLD3

--------------------

X 100 abc

X 100 def

Z 300 pqr

Outer Join:

-----------

FLD1 FLD2 FLD3

--------------------

X 100 abc

X 100 def

Y 200 " No entry for Key Y in table B so FLD3 is blank

Z 300 pqr