Discover - Selected Fields not reset with index pattern change

[w33ble]

In Discover, if you select a field in one index pattern:

Then change index patterns without removing that field, it sticks around in the new index pattern, even when it's not a valid field there:

[kuy]

When index patterns are changed, selected fields should be reset by default (savedSearch.columns or ['_source'])? or are there some exceptions?

[cwurm]

Want to bump this. It still happens in 5.0, and there's no way to remove the selected field without switching back to the index pattern it came from.

There's several options I can think of:

1. Reset the selected fields when the index pattern is changed (what @kuy suggested)
2. Remove only the selected fields that are not contained in the newly selected index pattern
3. Save selected fields for each index pattern (implicitly or explicitly)

Option 3 is a bigger change I guess and needs thinking about the user experience, while 1 or 2 would probably be easier to do.

[cwurm]

There actually is a button next to the column name, but it's tiny and appears only when hovering over it.

[marius-dr]

I did encounter this today and my first thought was: "hmm, why are these still here?". It would be nice to have it saved for each index, but for now it still is a bad experience for the user and just resetting it would make a big difference.

[marius-dr]

Looks the same in 4.x and 5.x, The selected field is not displayed in the upper right list, but it will still be displayed on the dashboard table as a column.

[tbragin]

Removing discuss label - we will triage this in the context of Discovery team.

[weltenwort]

Is this only limited to the columns? Other parts of the application state that relate to the available fields should probably also be reset when the index pattern changes, i.e. sorting, filters (see #9387), query. How would we justify resetting some but not others?

Discover could absolutely use an overhaul of the way the app state is managed, but then it almost feels like a breaking change instead of a bugfix.

[Bargs]

@weltenwort I tend to agree, I've left similar comments on other issues. In my mental model the index pattern is just one part of the search, and it should be possible to swap the index pattern without losing the rest of your search. Now that the New button correctly resets the columns, I wonder how useful this would be.

[bluikko]

Clicking "New" button before switching the index clears the selected fields... as per #10357

[lukasolson]

Closing this for now as you can now click the "New" button to clear things out, and some people may want this behavior if they have fields that are the same across index patterns.