XOR in Oracle

I had a situation where an XOR implementation was needed in a SELECT query. Since Oracle 10g doesnt have this operator predefined i did some gymnastics and ended up with this solution.

I decided to share this (among others) since human knowledge belongs to mankind

1. XOR in oracle

Example 1 - chars only

Eg we want to display results where ismale='1' XOR iscitizen='1' (ie either but not both)

Solution
SELECT ismale, iscitizen, (ismale + iscitizen) as xor
FROM tablename
WHERE ismale + iscitizen = 1;

NB: oracle will add(mathematical) chars as it would integers

Example 2 - varchars

Eg we want to display results where gender='male' XOR countryid='KE' (ie either but not both)

Solution
SELECT gender, countryid, (decode(gender,'male','1','0') + decode(countryid,'KE','1','0')) as xor
FROM tablename
WHERE (decode(gender,'male','1','0') + decode(countryid,'KE','1','0')) = 1;

NB: oracle will add chars as it would integers