How to get cursor query

Hi,

I have a long executing query via foreign data wrapper and on the remote server i can see that the query is fetching data from the cursor

=# select application_name, state, query from pg_stat_activity where pid = 15455;
application_name │ state │ query
──────────────────┼────────┼─────────────────────
postgres_fdw │ active │ FETCH 100 FROM c514 Is it possible to get query text corresponding to cursor c514?

One of the solution is to turn statement logging on (found it here http://www.postgresql.org/message-id/1361CEF686657C41A139AD8C3145632B44B33A8F@E2010-MB1.manord.com), but it works if i turn statement logging on before query execution. What can i do in case of connection to the server after the statement was executed?