Hello saama5,
This should return the lowest key that does not have a consecutive key:
SELECT MIN(keyName)
FROM tableName
where keyName <plus sign> 1 NOT IN
(SELECT keyName FROM tableName)
(In the third line between 'keyName' and '1', please insert the single character plus sign. It is not showing up in my preview, so I assume it will not show up in the posting either. I don't know the trick to get around this. Sorry)
Jennifer