Serious OutOfMemory issue while reading with mysql-connector-j-5.0.7 ...

Hi!

Yesterday I was supprised to get an out of memory exception when reading 
a big table rec by rec without any caching. The program died in 
stmt.executeQuery(), long before I can do anything with the records.

I've tried different connection options and debugged connector/j ... 
every time code runs into MysqlIO.readAllResults which can not work, if 
the table has more records than available in the jvm. More interesting - 
also server side prepared statements run into that readAll-routine?

Tested with
connector-j-5.0.3 + 5.0.7,
mysql db 5.0.41 + some older 5.0 on windows.

C:\Test\src>javac -cp ..\..\lib\jdbc\mysql-connector-java-5.0.7-bin.jar 
MySQLRead.java
C:\Test\src>java -cp ..\..\lib\jdbc\mysql-connector-java-5.0.7-bin.jar;. 
MySQLRead
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
        at com.mysql.jdbc.Buffer.getBytes(Buffer.java:198)
        at com.mysql.jdbc.Buffer.readLenByteArray(Buffer.java:318)
        at 
com.mysql.jdbc.MysqlIO.extractNativeEncodedColumn(MysqlIO.java:3567)
        at 
com.mysql.jdbc.MysqlIO.unpackBinaryResultSetRow(MysqlIO.java:3483)
        at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:1391)
        at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:2369)
        at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:451)
        at 
com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:2076)
        at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1451)
        at 
com.mysql.jdbc.ServerPreparedStatement.serverExecute(ServerPreparedStatement.java:1314)
        at 
com.mysql.jdbc.ServerPreparedStatement.executeInternal(ServerPreparedStatement.java:740)
        at 
com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1448)
        at MySQLRead.main(MySQLRead.java:23)

Regards
Paul

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import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

/**
 * @author Paul Palaszewski
 * @since 23.08.2007
 */
public class MySQLRead {
    public static void main(String[] args) {
        try {
            Class.forName("com.mysql.jdbc.Driver");
// tried
// jdbc:mysql://localhost:3306/test?jdbcCompliantTruncation=false&zeroDateTimeBehavior=convertToNull&useCursorFetch=true
// jdbc:mysql://localhost:3306/test?jdbcCompliantTruncation=false&zeroDateTimeBehavior=convertToNull
// jdbc:mysql://localhost:3306/test
// jdbc:mysql://localhost:3306/test?useServerPrepStmts=true
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?useServerPrepStmts=true", "root", "");
            PreparedStatement stmt = conn.prepareStatement("SELECT * FROM wb_absatz");
// tried with / without fetch size
            stmt.setFetchSize(50);
            ResultSet rs = stmt.executeQuery();
            long start = System.currentTimeMillis();
            int recCount = 0;
            while (rs.next()) {
                rs.getString(1);
                rs.getString(2);
                rs.getString(3);
                recCount++;
            }
            stmt.close();
            conn.close();
            long duration = System.currentTimeMillis() - start;
            System.out.println("Read " + recCount + " records in " + (duration / 1000.0) + "s");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}