Feature request #16432
Update the field list in layer.dataProvider().forceReload()
|Pull Request or Patch supplied:||No||Resolution:|
Once you load e.g. postgis table into QGIS, there is no way to reload its fields (e.g. after adding a column via psycopg or other concurrent connection), except reloading the whole project of course. The layer.dataProvider().forceReload() assumes the fields structure is constant and only reloads the records.
I noticed it when working with PostGIS, but I suspect it's a provider-independent issue.