Java database help [closed]

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Working my way through a chapter of study and I have been given code where there is two databases made, I have compiled the code and it works. I have no tried to tweek the code so its only one database, when it comes to the selecting the information and displaying it i am just getting a blank no output from it, where have i went wrong im guessing its somewhere in the selection of information from the DB?

Thanks

import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Enumeration;

public class FootballTeamDataBase
{
   Connection connection;
   Statement statement;
   ResultSet results;

    public FootballTeamDataBase() 
    {
        try
      {

         Class.forName("org.apache.derby.jdbc.ClientDriver");
      }

      catch (ClassNotFoundException cnfe)
      {
         System.err.println("Derby driver not found.");
      }

      try
      {

         // What drivers are there?
         System.out.println("Available drivers:");
         Enumeration<Driver> drivers = DriverManager.getDrivers();
         while (drivers.hasMoreElements())
         {
            System.out.println(drivers.nextElement());
         }
         System.out.println();


         connection = DriverManager.getConnection
               ("jdbc:derby://localhost:1527/MusicShop;create=true;user=admin;pass=admin");

         statement = connection.createStatement();


         try
         {
            statement.execute("drop table FootballTeam");
         }
         catch (SQLException e)
         {
            System.out.println("Table did not previously exist " + e);
         }

         // Now create the table.
         statement.execute("create table " +
               "FOOTBALLTEAM(" +
               "ID varchar(12) primary key not null, " +
               "POSITION varchar(24), " +
               "NAME varchar(24),") ;

      }
      catch (SQLException sqle)
      {
         System.err.println("Problem:" + sqle);
      }
   }

   public void addData()
   {
      try
      {
         statement.execute("insert into FOOTBALLTEAM values " +
               "('1',Keeper','Dale'");
         statement.execute("insert into FOOTBALLTEAM values " +
               "('2',Defender','Lewis'");
         statement.execute("insert into FOOTBALLTEAM values " +
               "('3','MIDFIELD','Jones'");
      }
      catch (SQLException sqle)
      {
         System.err.println("Problem populating data:" + sqle);
      }

   }

   public void showTeam()
   {
      try
      {
          // check the contents of the table
         System.out.println("DB contents:");
           // select all records
         statement.execute("select * from FOOTBALLTEAM");

          ResultSet results = statement.getResultSet();
         while (results.next())
         {     
            System.out.println(results.getString("ID") + "  " + results.getString("POSITION") + 
                    " = " + results.getString("NAME") );  
         }

      }

      catch (SQLException e)
      {
         // nothing wrong
      }
   }


}

any information regarding which database is it, what the program should do, input example and output (expected and actual outputs) will make this question much more understandable. — amit
– amit, Commented Jun 25, 2011 at 19:29
I don't see any piece of code where you close connection, statement and resultset. Maybe you should do this — maks
– maks, Commented Jun 25, 2011 at 19:35
Amit, It should check if the table exists already, if it does it removes it Output should be Table is created, but no content yet DB Contents: Table now populated with data DB contents: (Here i should get 1, Keeper, Lewis 2, defender, jones 3, midfielder, smith ) but i get nothing — user445714
– user445714, Commented Jun 25, 2011 at 19:45

Jesper · Accepted Answer · 2011-06-26 13:35:15Z

1

Looking at these lines, your SQL statements are malformed:

statement.execute("insert into FOOTBALLTEAM values " +
    "('1',Keeper','Dale'");
statement.execute("insert into FOOTBALLTEAM values " +
    "('2',Defender','Lewis'");
statement.execute("insert into FOOTBALLTEAM values " +
    "('3','MIDFIELD','Jones'");

Note that the SQL statements contain an opening ( but no closing ). Change it like this:

statement.execute("insert into FOOTBALLTEAM values " +
    "('1',Keeper','Dale')");
statement.execute("insert into FOOTBALLTEAM values " +
    "('2',Defender','Lewis')");
statement.execute("insert into FOOTBALLTEAM values " +
    "('3','MIDFIELD','Jones')");

Likewise here, this does not look like a complete SQL statement:

// Now create the table.
statement.execute("create table " +
    "FOOTBALLTEAM(" +
    "ID varchar(12) primary key not null, " +
    "POSITION varchar(24), " +
    "NAME varchar(24),") ;

answered Jun 26, 2011 at 13:35

Jesper

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2 Comments

user445714 Over a year ago

Thanks Jesper, now fixed them problems but still no change

Ant Kutschera Over a year ago

There is no opening quote for Keeper or Defender either!

Ant Kutschera · Accepted Answer · 2011-06-25 19:56:53Z

1

Perhaps you have not committed the data? connection.setAutoCommit(true), or, begin and end the transaction: JDBC Transactions

answered Jun 25, 2011 at 19:56

Ant Kutschera

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