SQLException: how do I know where I went wrong?

Question

I just revolutioned the database I was using for my tomcat application, switching from MyIsam to InnoDB.
But as soon as I tried an insert I got an SQLException.
this is part of the code (which is called from a servlet):
    public void saveInitialize(String gameName) throws ClassNotFoundException, SQLException {
        Connection con = null;
     Statement stmt = null;
     PreparedStatement pstmt = null;
     ResultSet rs = null;
     try {
         con = DBConnect.connect("GAMES");
         con.setAutoCommit(false);
         stmt = con.createStatement();
         int IDGioco = 1;
         rs = stmt.executeQuery("SELECT ID FROM GAMES ");
         while (rs.next()) {
          IDGioco = rs.getInt("ID") + 1;
         rs.close();
         stmt.executeUpdate("INSERT INTO GAMES VALUES (" + IDGioco + ", '" + gameName + "', " + numeroPeriodi + ", " + numeroAziende + ", " + numeroProdotti + ", " + periodiGiocati + ")");
         for (int i = 1; i <= numeroAziende; i++) {
             stmt.executeUpdate("INSERT INTO AZIENDE " +
              "VALUES (" + i + ", '" + nomeAzienda[i] + "', ENCODE('" + passwordAzienda[i] + "','tbg'), " + IDGioco + ", " + periodiInseriti[i] + ")");
         for (int j = 1; j <= numeroProdotti; j++) {
             stmt.executeUpdate("INSERT INTO PRODOTTI " +
              "VALUES (" + j + ", '" + nomeProdotto[j] + "', " + IDGioco + ")");
         pstmt = con.prepareStatement("INSERT INTO P_UNITA VALUES ( ?, ?, ?, ?)");
         pstmt.setInt(1, parametroUnitaPrezzo);
         pstmt.setInt(2, parametroUnitaInvestimenti);
         pstmt.setInt(3, parametroUnitaPezzi);
         pstmt.setInt(4, IDGioco);
         pstmt.executeUpdate();
         pstmt.close();
         pstmt = con.prepareStatement("INSERT INTO P_DEFAULT_PRODOTTO VALUES ( ?, ?, ?, ?, ?, ?, ?, ?)");
         for (int j = 1; j <= numeroProdotti; j++) {
             pstmt.setInt(1, parametroDefaultPrezzo[j]);
             pstmt.setInt(2, parametroDefaultPromozione[j]);
             pstmt.setInt(3, parametroDefaultPubblicita[j]);
             pstmt.setInt(4, parametroDefaultPrevisioneDiVendita[j]);
             pstmt.setInt(5, parametroDefaultDesign[j]);
             pstmt.setInt(6, parametroDefaultTecnologia[j]);
             pstmt.setInt(7, IDGioco);
             pstmt.setInt(8, j);
          pstmt.addBatch();
         pstmt.executeBatch();
         pstmt.close();
/// etc. etc. etc.this is the error message I get:
java.sql.SQLException: Syntax error or access violation: You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near '800. 600. 1)' at line 1 at com.mysql.jdbc.MysqlIO.sendCommand(Unknown Source) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(Unknown Source) at com.mysql.jdbc.Connection.execSQL(Unknown Source) at com.mysql.jdbc.PreparedStatement.executeUpdate(Unknown Source) at com.mysql.jdbc.PreparedStatement.executeUpdate(Unknown Source) at Game.saveInitialize(Game.java:7759) at SingletonGame.syncInitialize(SingletonGame.java:71) at SaveNewGame.doPost(SaveNewGame.java:316) at javax.servlet.http.HttpServlet.service(HttpServlet.java:760) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at
etc. etc. etc.
how do I know where I went wrong (the insert code is about 1200 lines)?
thank you
alessandro

Answer 1

While not related to your problem, I did notice that you're inserting into columns without specifying the column names, ie.
         stmt.executeUpdate("INSERT INTO GAMES VALUES (" + IDGioco + ", '" + gameName + "', " + numeroPeriodi + ", " + numeroAziende + ", " + numeroProdotti + ", " + periodiGiocati + ")");While technically it's not an error, it's really easy to introduce a bug into your code. There's no guarantee that the order of columns will always be the same as when you created the table. It's much better to do something like "insert into games (col1,col2,col3...) values(...)".