Joining tables on fields with varying lengths - response (2) by dnoeth

You don't have to care about CHARs or VARCHARs, because trailing spaces simply don't matter, e.g. '0123' and '0123        ' compare equal.
But the leading zeroes (or leading blanks) cause trouble and you need to get rid of them. You should use Raja's approach, just change BOTH to LEADING.