Cursor returned from procedure ignores setFetchSize() on CallableStatement

From: "Brian G(dot) Huber" <brianghuber(at)yahoo(dot)com>
To: <pgsql-sql(at)postgresql(dot)org>
Subject: Cursor returned from procedure ignores setFetchSize() on CallableStatement
Date: 2004-06-08 05:40:14
Message-ID: 001a01c44d1b$131f7160$6400a8c0@bghthinkpad
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Hello all -

I need to return large result sets and therefore need a cursor with a small
fetch size (to avoid caching the entire query at once). However, it appears
that when a cursor is returned from a callable statement setFetchSize is
ignored.

I set up a query that crashes with outofMemoryError if entire query is
cached. I am able to sucsessfully use a Statement and setFetchSize() to
avoid the crash. However, when I put the code in a procedure, the
outofMEmoryError throws before I even try to access the result set,
indicating that the entire query is caching. This is true with or without
calling setFetchSize on the ResultSet in addition to the CallableStatement.

Is this a bug or am I doing something wrong? Any comments greatly
appreciated. Thanks

Client
Code------------------------------------------------------------------------
-----------

cn.setAutoCommit(false);
CallableStatement proc = cn.prepareCall("{ ? = call reffunc2('cursor1') }");
proc.setFetchSize(100);
proc.registerOutParameter(1, Types.OTHER);
proc.execute();
rds = (ResultSet) proc.getObject(1);
rds.setFetchSize(100);
while (rds.next()){
...
}
Function--------------------------------------------------------------------
---------------------------------------------

CREATE OR REPLACE FUNCTION public.reffunc2(refcursor) RETURNS refcursor AS '
BEGIN
OPEN $1 FOR SELECT ...<Large Query>...;
RETURN $1;
END;
' LANGUAGE 'plpgsql' VOLATILE;

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