Trying to return the corresponding itemno for a given icitem.altset #.   

Normally, I'd just write a SQL statement such as:

select [icitem].[itemno] from [icitem] where [icitem].[altset]

but, alset is an integer, and I can't find a column in icitem that's corresponds to the integer (looked in the provided data dictionary, not help.)   My thought is its a row #or some type of hidden key/index in the table, but can't find any documentation on it.  

Using Sage300 2016PU1 w/ Connector.