Re: [JDBC] Bug #886: jdbc "update row" can mess up other

Patch Applied,

Thanks,

Dave
On Mon, 2003-11-03 at 04:45, Kris Jurka wrote:
> Half of this bug was fixed at some point, but an exception is still thrown
> when calling rs.afterLast() and then rs.previous(). Attached is a
> regression test addition and the appropriate fix. Sorry for the extreme
> delay in response and thanks for the thorough report.
>
> Kris Jurka
>
> On Fri, 24 Jan 2003 pgsql-bugs(at)postgresql(dot)org wrote:
>
> > Andrew Fyfe (afyfe(at)bigtribe(dot)com) reports a bug with a severity of 3
> > The lower the number the more severe it is.
> >
> > Short Description
> > jdbc "update row" can mess up other columns
> >
> > Long Description
> > The attached program when run gives me the following output
> >
> > DatabaseProductName: PostgreSQL
> > DatabaseProductVersion: 7.3.1
> > DriverName: PostgreSQL Native Driver
> > DriverVersion: PostgreSQL 7.3.1 JDBC3 jdbc driver build 106
> > --- Forward ---
> > 1: Colombian 7.99
> > 2: French_Roast 9.99
> > --- Backward ---
> > 2: French_Roast 9.99
> > 1: Colombian 7.99
> > --- Update Row 2 ---
> > --- Forward ---
> > 1: Colombian 7.99
> > 2: Colombian 10.99
> >
> > Note that the update of the price in row 2 caused jdbc to misrepesent the name. If one does not run through the rows backward (give the arg "b" when running the code), then the output is correct:
> >
> > --- Forward ---
> > 1: Colombian 7.99
> > 2: French_Roast 9.99
> > --- Update Row 2 ---
> > --- Forward ---
> > 1: Colombian 7.99
> > 2: French_Roast 10.99
> >
> > Suppressing the first forward pass through the data (giving "f" or "fb" to suppress both) will cause an exception to be thrown.
> >
> > Note that another forward pass after the backward makes the problem go away.
> >
> > Sample Code
> > import java.util.*;
> > import java.sql.*;
> >
> > class pgbug
> > {
> > static String url = "jdbc:postgresql://localhost/cdb";
> > static String driver = "org.postgresql.Driver";
> > static String userName = "cdb";
> > static String password = "cdb";
> >
> > public static void print(ResultSet rs) {
> > try {
> > String s = rs.getString("COF_NAME");
> > float n = rs.getFloat("PRICE");
> > int rowNum = rs.getRow();
> > System.out.println(rowNum + ":\t" + s + "\t" + n);
> > } catch (SQLException sqlEx) { /* ignore */
> > System.out.println("print ResultSet failed");
> > }
> > }
> >
> > public static void forward(ResultSet rs) {
> > try {
> > System.out.println("--- Forward ---");
> > rs.beforeFirst();
> > while (rs.next()) {
> > print(rs);
> > }
> > } catch (SQLException sqlEx) { /* ignore */
> > System.out.println("print ResultSet failed");
> > }
> > }
> >
> > public static void backward(ResultSet rs) {
> > try {
> > System.out.println("--- Backward ---");
> > rs.afterLast();
> > while (rs.previous()) {
> > print(rs);
> > }
> > } catch (SQLException sqlEx) { /* ignore */
> > System.out.println("print ResultSet failed");
> > }
> > }
> >
> > public static void main(String args [])
> > throws Exception
> > {
> >
> > Connection conn = null;
> > Statement stmt = null;
> >
> > try {
> > // Load the mysql JDBC driver
> > Class.forName(driver).newInstance();
> >
> > // Connect to the database
> > Properties props = new Properties();
> > props.put("user", userName);
> > props.put("password", password);
> > props.put("loglevel", "0");
> > conn = DriverManager.getConnection(url, props);
> >
> > // Create a Statement
> > stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
> > ResultSet.CONCUR_UPDATABLE);
> >
> > DatabaseMetaData meta = conn.getMetaData();
> > System.out.println("DatabaseProductName: " +
> > meta.getDatabaseProductName());
> > System.out.println("DatabaseProductVersion: " +
> > meta.getDatabaseProductVersion());
> > System.out.println("DriverName: " +
> > meta.getDriverName());
> > System.out.println("DriverVersion: " +
> > meta.getDriverVersion());
> >
> > try {
> > stmt.executeUpdate("drop table coffees");
> > } catch (SQLException sqlEx) { /* ignore */
> > System.out.println("drop table failed");
> > }
> >
> > // create the table
> > String createTableCoffees = "create table coffees " +
> > "(COF_NAME VARCHAR(32) primary key, PRICE FLOAT)";
> > try {
> > stmt.executeUpdate(createTableCoffees);
> > } catch (SQLException sqlEx) { /* ignore */
> > System.out.println("create table failed");
> > }
> >
> > stmt.executeUpdate("insert into coffees " +
> > "VALUES ('Colombian', 7.99)");
> > stmt.executeUpdate("insert into coffees " +
> > "VALUES ('French_Roast', 9.99)");
> >
> > // Select from the test table
> > String query = "select cof_name, price from coffees";
> > ResultSet rs = stmt.executeQuery(query);
> >
> > if (args.length == 0 || args[0].indexOf('f') < 0) {
> > forward(rs);
> > }
> > if (args.length == 0 || args[0].indexOf('b') < 0) {
> > backward(rs);
> > }
> >
> > if (rs.absolute(2)) {
> > System.out.println("--- Update Row 2 ---");
> > rs.updateFloat("PRICE", 10.99f);
> > rs.updateRow();
> > }
> >
> > forward(rs);
> > } finally {
> > if (stmt != null) {
> > try {
> > stmt.close();
> > }
> > catch (SQLException sqlEx) {
> > System.out.println("closing statement failed");
> > }
> > }
> > if (conn != null) {
> > try {
> > conn.close();
> > }
> > catch (SQLException sqlEx) {
> > System.out.println("closing connection failed");
> > }
> > }
> > }
> >
> > }
> > }
> >
> >
> > No file was uploaded with this report
> >
> >
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> >
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