"nested transaction" - encosing statement gets closed when the enclosed statement is closed

I have experienced problems using the JDBC type 2 and type 3
drivers for 8.1 (postgresql-8.1-408.jdbc3.jar,
postgresql-8.1-408.jdbc2.jar) against PostgreSQL 8.1.5.

I am running through the ResultSet of a select query that
involves a join, and for each result I do a lookup on one
of the tables in the join.

   Statement stmt = conn.createStatement();
   Statement stmtchk = conn.createStatement();
     ....
   ResultSet rs = stmt.executeQuery(searchquery);
     ....
   while (rs.next()) {
       .....

For the lookup, I do

     ResultSet rsch = stmtchk.executeQuery(checkquery);
     while (rsch.next()) {
       maxrefid = rsch.getInt("max");
     }
     rsch.close();
     stmtchk.close(); // leads to the closing of stmt!!!

     ...
   } // while


For some reason, the ResultSet that I am looping through is
closed by the lookup, and I receive the following exception:
"SQL Exception (working on resultset)! (selecttempmaps):
  org.postgresql.util.PSQLException: This statement has been closed."

In PostgreSQL 7.4.1 I did not experience this behaviour.

As you can see, I am using a new statement for the lookup.
I have also tried to create a new connection for the lookup,
but the problem persists.

If I comment out stmtchk.close(), the application runs as
it did in 7.4.1.


Is this expected behaviour?


--
Håvard Tveite
Department of Mathematical Sciences and Technology, UMB
Drøbakveien 14, POBox 5003, N-1432 Ås, NORWAY
Phone: +47 64965483 Fax: +47 64965401 http://www.umb.no/imt