Bulk update of custom field fails with unusual error

[Greg Newman]

I'm trying to do a bulk csv upload of a custom field on sub task issues and the fail with error

ERROR - Unexpected failure occurred. Importer will stop immediately. Data may be in an unstable state: Failed to remove subtasks [CARS-532] parents. A parent of a subtask cannot be removed.

The input csv file contains three fields issue Key, Summary, Custom field and looks like this 

Summary,Issue key,Custom field (SP Name)
"Record,  xxxxx- SP",CARS-532,xxxxx_CRYSTAL_10

Import is done through admin external data import and the tree fields are mapped accordingly.

The record to be updated does not have any subtasks.

I'm really baffled, any thoughts? I have about 150 to update, so would rather not do them manually.

[John Funk · Accepted solution]

Hi Greg,

What issue type is CARS-532? And is that a sub-task type of issue type?

[Greg Newman]

Hi John, 532 is a sub-task of a Task

[John Funk]

Do you have a value in the spreadsheet for the parent for issues CARS-532? If not, you need one. That appears to be the problem. 

[Greg Newman]

Thanks John ,I'll take a look at that now

[Greg Newman]

That was confusing, I exported all issues to a csv  and the sub task didn't have a parentid, so i tried an update again using the issueid of the parent task in the parentid field and received the same error. 

I then want back to the original file i'd used to load the project and noticed I had given all of the parent issues an issueid on the load. Unfortunately this external issueid doesn't appear to be visible on a full export file, however I still have the original file, so i could lookup the id used and placing that in the parentid field meant the update worked fine.

It's strange that the external id isn't exported on a full export, as I would have been unable to do the update without the original load file.

Thanks for your help