Creating sub tasks for CSV imports

[Sierra]

Referring to Import data from a CSV file | Atlassian Support 

Example:

I want my subtasks to be line 5,6,7,8 of 4. How do I format this correctly ? 

[Nic Brough -Adaptavist-]

Give every issue in your sheet a unique identifier in the "issue id" column.  That can be as simple as 1, 2, 3 etc, but as it's going to be imported into the "external issue id" field, I'd recommend something a bit more text based, to show where it came from.

For each sub-task, work out what the "issue id" is for their parent issue in the file, and fill that in on their "parent ID" column on their row.

For example

Summary, issue id, parent id

Subtask1, abc1, abc4

Subtask2, abc2, abc3

Story1, abc3,

Story2, abc4,

Story3, abc5,

Will net you three stories, two with a single subtask each.