When creating a taxonomy via import, or updating one via re-import, the “id” column is required. In addition, it must be unique for every row. There are two reasons why such IDs are required.
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For example, if you uploaded this taxonomy and used it to tag content in your courses:
ID | Value |
|---|---|
1 | Untied States |
3 | Candana |
Then you fixed the spelling to create this new version of the taxonomy, and re-imported it:
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… because the ID of the first tag is the same (1), any content that was tagged with “Untied States” will now be fixed to show “United States”. But because the ID of the second tag has been changed, it is treated as a totally new tag - all instances of the “Candana“ tag will be deleted, and a new “Canada” tag will be created in the taxonomy, but no content will have that tag yet.
By keeping the ID the same (or not), you can control what will happen with new versions of the taxonomy - adding, renaming, moving, and deleting tags as needed. (Note that during the re-import workflow, you’ll get a chance to preview what changes will be applied before you finalize the update. That’s a good time to double-check that the right thing - rename or delete - is about to happen.)
If in doubt, a good rule of thumb is to never change the ID once a tag has been created, unless you’re certain you want to delete all occurrence of that tag and re-create a new similar tag from scratch.
Matching external systems/taxonomies
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