Re: [BUGS] Bug #886: jdbc "update row" can mess up other - Mailing list pgsql-jdbc

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@postgresql.org wrote:
>
> > Andrew Fyfe (afyfe@bigtribe.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
rowsbackward (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
tobe 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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