BUG #1240: memory leak in JDBC driver build 215

The following bug has been logged online:

Bug reference: 1240
Logged by: Roland Walter

Email address: rwa(at)mosaic-ag(dot)com

PostgreSQL version: 7.4.3

Operating system: SuSE Linux 9.0, Windows CYGWIN, J2SDK 1.4.2_x

Description: memory leak in JDBC driver build 215

Details:

Hello!

I used the JDBC driver build 215 that was given by postgresql 7.4.5. (The
webinterface for bug reports
has not the version 7.4.5 yet.)

I wanted to execute the following statement with JDBC on a database table
named transaction with 3.945.773 rows:

SELECT * FROM transaction WHERE transaction_date >=
to_timestamp('01.01.2002', 'DD.MM.YYYY') AND transaction_date <
to_timestamp('01.01.2003', 'DD.MM.YYYY')

But I got the following error message from the JVM:

java.lang.OutOfMemoryError

Here the java-code:

stmt = con.createStatement();
log.debug("executing SQL-Stmt: " + stmtString);
rs = stmt.executeQuery(stmtString);
log.debug("getting metadata");
ResultSetMetaData rsMeta = rs.getMetaData();

And here the output I got:

328 [main] DEBUG com.mosaicag.rwa.dbutil.standard.DefaultCsvExport -
executing SQL-Stmt: SELECT * FROM transaction WHERE transaction_date >=
to_timestamp('01.01.2002', 'DD.MM.YYYY') AND transaction_date <
to_timestamp('01.01.2003', 'DD.MM.YYYY')
java.lang.OutOfMemoryError
Exception in thread "main"

As you can see, the log.debug("getting metadata"); was
never reached. A count with the same where-clause gave 387.665 rows, that
should have been iterated with a
while(rs.next()) loop. The JVM used the standard heap size, there were no
big memory allocations in the previous code.

The table definition is as follows:

create table transaction (
transaction_id bigint not null,
bc_id bigint,
recipient_iln varchar(20) not null,
transaction_date timestamp,
transaction_type varchar(20),
transaction_state varchar(20),
productive char(2),
remark varchar(255),
origin char(2),
cc_trans_id numeric(38),
constraint xpktransaction primary key (transaction_id));