column information from view

Hello,

I'm trying to generate a table with information on columns from a
temporary view that simply selects a subset of columns from a persistent
view in a given schema.  The persistent view joins a number of tables
with columns that may or may not have a description entered.  I need a
table with a list of columns from the temporary view, and the matching
descriptions from the underlying persistent view.

Here's my attempt at listing the temporary view's columns and respective
descriptions:

SELECT cols.ordinal_position, cols.column_name,
  col_description(cl.oid, cols.ordinal_position::INT)
FROM pg_class cl, information_schema.columns cols
WHERE cols.table_catalog='dbname' AND cols.table_schema='some_schema' AND
  cols.table_name = 'persistent_view' AND cols.table_name = cl.relname
ORDER BY cols.ordinal_position::INT;

The problem, of course, is that it lists columns from the persistent
view, instead of the subset of them in the temporary view.  Is there a
better way to do that?  Hopefully this makes sense.

Thanks,
--
Seb