You need to edit the datamodel for your servicedesk database in Xtraction, so that Xtraction knows about "the new bit of data" in the first place.
The following should help you out here:
- Feature - Data Model Editor Schema View (This is an E-learning module)
This thread here contains some links as well - Re: Where is Data Model Editor Training? -- which I've included above!
that should be really all that there is to it.
XTraction essentially needs to have a map for "data X exists in service desk database" -- if you add new fields, XTraction needs to be told that this new data exists.
It's quite easy to use / do.
That said - ALWAYS make a safety backup of your datamodel file BEFORE editing it (and another backup after a SUCCESSFUL change!) .