Somehow I can’t select the fields from the selected source. It shows fields from another source. This did work, suddenly the graphs using this blendsource don’t work anymore, because dimensions are supposedly invalid. I think these are invalid because it can’t find the fields in the other source. See in image, the selected source and the source I can pick fields from are different.
How to Fix It
1. Refresh the Fields
Before changing the blend, try a hard refresh of the data schema.
Go to Resource > Manage added data sources.
Find the individual sources used in the blend and click Edit.
Click Refresh Fields at the bottom left. If any fields have changed, apply the changes.
2. Force-Update the Blend Configuration
If the UI is showing fields from the wrong source, you need to “nudge” the blend editor:
Select a chart using the blend and click the Edit icon (pencil) next to the Blend Data source.
Toggle the Join: Temporarily change the Join operator (e.g., from Left Join to Inner Join) and then change it back. This often forces the UI to re-pull the field lists for all joined tables.
Check the “Hide” status: Ensure the fields you are looking for haven’t been accidentally hidden in the blend configuration screen.
3. Re-select the Source within the Blend
If the “Selected Source” and “Available Fields” still don’t match:
In the Blend Editor, remove the problematic table (the one showing the wrong fields).
Immediately re-add that same data source back into the blend.
Re-map your Join Keys. This usually clears the cache that causes the UI misalignment.
4. Use the “Add Field” Workaround
If you can see the source but not the fields, try clicking Add Dimension and start typing the name of the field manually. Sometimes the search index works even when the visual list is bugged.
A Quick Tip on Prevention
Blends are sensitive to Data Type changes. If Field_ID was a Number yesterday and is now a Text string in your source, the blend will break silently. Ensure that the Join Keys across all sources have the exact same data type in the individual data source settings.
Thanks for your reply. It seems this is only a visual bug, not causing my graph not to load.
Options 2 and 4 seemed to fix the visual bug. Later the bug reappeared btw, so no permanent fix.
What did solve my graph not loading was removing some numeric columns in the blend which had multiple empty fields. These fields where irrelevant for the blend.