Database

SELECT *
FROM TableA A 
INNER JOIN TableB B
ON A.Field1=B.Field1
OR A.Field2=B.Field2

SELECT * FROM TableA

ID Field1 Field2
-- ------ ------
10 A      E
11 E      D
12 A      D

SELECT * FROM TableB

ID Field1 Field2
-- ------ ------
20 A      B
21 C      D

ID Field1 Field2 ID Field1 Field2
10 A      E      20 A      B      <-- I want this row
11 E      D      21 C      D      <-- I want this row
12 A      D      20 A      B      <-- I want this row
12 A      D      21 C      D      <-- I don't want this row

WITH cte1 AS
(
SELECT A.ID aID
, A.Field1 aField1
, A.Field2 aField2
, B.ID bID
, B.Field1 bField1
, B.Field2 bField2
FROM TableA A
INNER JOIN TableB B
ON A.Field1=B.Field1
)
, cte2 AS
(
SELECT A.ID aID
, A.Field1 aField1
, A.Field2 aField2
, B.ID bID
, B.Field1 bField1
, B.Field2 bField2
FROM TableA A 
INNER JOIN TableB B
ON A.Field2=B.Field2
)
  SELECT *
  FROM cte1
UNION ALL
  SELECT C2.* 
  FROM cte2 C2
  LEFT OUTER JOIN cte1 C1
  ON C2.aID=C1.aID
  WHERE C1.aID IS NULL