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.
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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 occurrences of that tag and re-create a new similar tag from scratch.
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