Data in import set table but can not be transformed into target table

[Cheng Luo]

I am using a dev instance dev64918.service-now.com to load some system configuration data from xml file into cmdb using import set. After loading, I can see the import set table was updated with records properly. However when I tried to use transform map(field map) to transform those data into target table(user defined). I can see the record in import set table was changed into Processed state. However the target table was still empty. Screen shot for the import set table and transform record attached. Anyone can help on this?

[SELECT Username]

As far as uniquely identifying a record, the short answer is that you let the IRE do that.  That's the "I" in "IRE"...as it stands for "Identification".  

It's best to get a firm, foundational understanding of the IRE before attempting any imports into the CMDB.

Identification and Reconciliation engine (IRE) | ServiceNow Docs

The long answer is that you need to have the correct Identification rules in place, map correctly, and then have reconciliation rules in place to determine what attributes can be updated by which CMDB Sources.

There's about a 100% chance that writing directly to the CMDB with an Import Set without using the IRE will cause you problems down the road, so it's really worth the effort on the front end to understand the pieces and implement them correctly at the beginning.

[SELECT Username]

First and foremost, it appears that you've created a custom CI class that doesn't extend from "Computer" (more specifically, "Server") which is a bad practice for this use case. Why not use the baseline class for zOS Server, "cmdb_ci_ibm_zos_server"?  You'll note that attributes like "Name" are available in this class (derived from the parent).

That said, I am with @Sean Duhaime in that no import should ever write to the CMDB without going through the IRE.  Here's a "Docs" link that will give an easier way than creating the payload yourself by using an onBefore script:

Apply CI Identification and Reconciliation to Import Sets | ServiceNow Docs

[SELECT Username]

Update: It appears from the transform map that you're using a custom class:

But the schema map screenshot shows the baseline class.  Could it be that you've got two tables and that you aren't seeing the updates because the transform map is pointing to the wrong one and you're looking for the records on the correct one?

I would still suggest that it should absolutely go through the iRE, but maybe your issue is related to this?