SELECT *
  FROM t1, t2
  WHERE t1.col1(+) ^= t2.col1;

Note: col1 is assumed to be CHAR(4) type

SELECT *
  FROM t1, t2
  WHERE t1.col1(+) != t2.col1;

Note: col1 is assumed to be CHAR(4) type

Feature differences

Oracle database

The ^= comparison operator can be specified.

Fujitsu Enterprise Postgres

The ^= comparison operator cannot be specified.

Conversion procedure

Convert using the following procedure:

1. Locate the places where the keyword "^=" is used.

2. Ensure that the keyword, "(+)", is either on the right or left-hand side.

3. Change "^=" to " !=".