Hi @Retired_mod, 

But in this case I would have to qualify the column that was defined in the select because it is the one that was no longer used when adding a table in the join that has exactly the same column name.

I don't know if there is a standard identifier that can be used to indicate that the column I am referencing is the LCA.

I got around it by adding a 'local -' prefix to the name of each column, but I found Databricks' behavior to be too risky in this case, since including a new column in a table can change the behavior of existing queries.