I am working on something that requires representing a SRF return column in pg_proc and being able to retrieve it, retrieve the name of the column and make a ColumnRef node from it.
The catch here are aliases:
SELECT generate_series(1,100) AS a ORDER BY a;
I need to know that the return column of generate_series is being referred as a in this query (hence tlist, sortClause will have 'c').
I discussed and think that a way can be to have position of column rather than the actual name but that raises the question of the functionality needed for back resolving position to name (to make a ColumnRef node) and then infer that the column is being referred as an alias in this query.