This is a question about QGIS: I am working locally (no connection to servers or databases) with some maps data which I have imported as a non-visible CSV layer. These were merged against some census data and a derived variable (proportion) was created using the field calculator. I used this to shade the census tracts in a choropleth. I saved my session and called it a day.
When I came back to reload my session, all my previous layers still existed, and the geocoded points remained. However, the choropleth shadings were absent. I opened up the field calculator to look at those data and did not see my derived field. When I tried to regenerate this value, the field calculator throws an error that the field name is not unique. But still I cannot find the field.
Is there a way for me to recover this field?