Cannot write to the database

Question

I am using MySql 4.0 with Kodo.
For the tutorials I can get pretty good result. But when I tried my own
database, I can only browse but cannot write. when I write a new data
item, the below exceptions popped up:
kodo.util.FatalDataStoreException: The transaction has been rolled back.
See the nested exceptions for details on the errors that occurred.
     at
kodo.runtime.PersistenceManagerImpl.throwFlushException(PersistenceManagerImpl.java:1297)
     at
kodo.runtime.PersistenceManagerImpl.flush(PersistenceManagerImpl.java:1159)
     at
kodo.runtime.PersistenceManagerImpl.flushSafe(PersistenceManagerImpl.java:1042)
     at
kodo.runtime.PersistenceManagerImpl.beforeCompletion(PersistenceManagerImpl.java:969)
     at kodo.runtime.LocalManagedRuntime.commit(LocalManagedRuntime.java:69)
     at
kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:629)
     at reversetutorial.Finder.executeCreatQuery(Finder.java:108)
     at reversetutorial.Finder.main(Finder.java:44)
NestedThrowablesStackTrace:
kodo.util.DataStoreException: 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 'key, value) VALUES ('test', '50')' at line 1
{prepstmnt 849515 INSERT INTO ns_config (key, value) VALUES (?, ?)
[reused=0]} [code=1064, state=42000]
     at
kodo.jdbc.sql.DBDictionary.newDataStoreException(DBDictionary.java:3400)
     at kodo.jdbc.sql.SQLExceptions.getDataStore(SQLExceptions.java:77)
     at kodo.jdbc.sql.SQLExceptions.getDataStore(SQLExceptions.java:63)
     at kodo.jdbc.sql.SQLExceptions.getDataStore(SQLExceptions.java:43)
     at
kodo.jdbc.runtime.PreparedStatementManager.flush(PreparedStatementManager.java:210)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:220)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:95)
     at kodo.jdbc.runtime.JDBCStoreManager.flush(JDBCStoreManager.java:614)
     at
kodo.runtime.DelegatingStoreManager.flush(DelegatingStoreManager.java:153)
     at
kodo.runtime.PersistenceManagerImpl.flush(PersistenceManagerImpl.java:1159)
     at
kodo.runtime.PersistenceManagerImpl.flushSafe(PersistenceManagerImpl.java:1042)
     at
kodo.runtime.PersistenceManagerImpl.beforeCompletion(PersistenceManagerImpl.java:969)
     at kodo.runtime.LocalManagedRuntime.commit(LocalManagedRuntime.java:69)
     at
kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:629)
     at reversetutorial.Finder.executeCreatQuery(Finder.java:108)
     at reversetutorial.Finder.main(Finder.java:44)
NestedThrowablesStackTrace:
com.solarmetric.jdbc.ReportingSQLException: 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 'key, value) VALUES ('test', '50')' at
line 1 {prepstmnt 849515 INSERT INTO ns_config (key, value) VALUES (?, ?)
[reused=0]} [code=1064, state=42000]
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.wrap(LoggingConnectionDecorator.java:124)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.access$600(LoggingConnectionDecorator.java:19)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator$LoggingConnection$LoggingPreparedStatement.executeUpdate(LoggingConnectionDecorator.java:728)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
kodo.jdbc.runtime.JDBCStoreManager$CancelPreparedStatement.executeUpdate(JDBCStoreManager.java:1716)
     at
kodo.jdbc.runtime.PreparedStatementManager.flushInternal(PreparedStatementManager.java:235)
     at
kodo.jdbc.runtime.PreparedStatementManager.flush(PreparedStatementManager.java:206)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:220)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:95)
     at kodo.jdbc.runtime.JDBCStoreManager.flush(JDBCStoreManager.java:614)
     at
kodo.runtime.DelegatingStoreManager.flush(DelegatingStoreManager.java:153)
     at
kodo.runtime.PersistenceManagerImpl.flush(PersistenceManagerImpl.java:1159)
     at
kodo.runtime.PersistenceManagerImpl.flushSafe(PersistenceManagerImpl.java:1042)
     at
kodo.runtime.PersistenceManagerImpl.beforeCompletion(PersistenceManagerImpl.java:969)
     at kodo.runtime.LocalManagedRuntime.commit(LocalManagedRuntime.java:69)
     at
kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:629)
     at reversetutorial.Finder.executeCreatQuery(Finder.java:108)
     at reversetutorial.Finder.main(Finder.java:44)
java.sql.SQLException: 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 'key, value) VALUES ('test', '50')' at line 1
     at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2921)
     at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1570)
     at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1665)
     at com.mysql.jdbc.Connection.execSQL(Connection.java:2978)
     at com.mysql.jdbc.Connection.execSQL(Connection.java:2902)
     at
com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:930)
     at
com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1159)
     at
com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1076)
     at
com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1061)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
com.solarmetric.jdbc.PoolConnection$PoolPreparedStatement.executeUpdate(PoolConnection.java:358)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator$LoggingConnection$LoggingPreparedStatement.executeUpdate(LoggingConnectionDecorator.java:724)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
     at
kodo.jdbc.runtime.JDBCStoreManager$CancelPreparedStatement.executeUpdate(JDBCStoreManager.java:1716)
     at
kodo.jdbc.runtime.PreparedStatementManager.flushInternal(PreparedStatementManager.java:235)
     at
kodo.jdbc.runtime.PreparedStatementManager.flush(PreparedStatementManager.java:206)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:220)
     at kodo.jdbc.runtime.UpdateManagerImpl.flush(UpdateManagerImpl.java:95)
     at kodo.jdbc.runtime.JDBCStoreManager.flush(JDBCStoreManager.java:614)
     at
kodo.runtime.DelegatingStoreManager.flush(DelegatingStoreManager.java:153)
     at
kodo.runtime.PersistenceManagerImpl.flush(PersistenceManagerImpl.java:1159)
     at
kodo.runtime.PersistenceManagerImpl.flushSafe(PersistenceManagerImpl.java:1042)
     at
kodo.runtime.PersistenceManagerImpl.beforeCompletion(PersistenceManagerImpl.java:969)
     at kodo.runtime.LocalManagedRuntime.commit(LocalManagedRuntime.java:69)
     at
kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:629)
     at reversetutorial.Finder.executeCreatQuery(Finder.java:108)
     at reversetutorial.Finder.main(Finder.java:44)
Exception in thread "main"
This is not a problem of Database version.
I found the sql statement that Kodo generated is like:
insert into ns_config (key, value) values ("test","50")
this is not correct, the correct should be:
insert into ns_config (`key`, `value`) values ('test','50')
but I found the script created with reversemappingtool is all correct
(with the ` symbol in the statement).
So this problem really caught me.
ps: below is the java code I use for testing:
1. Finder.java
package reversetutorial;
import java.lang.reflect.Constructor;
import java.util.*;
import javax.jdo.*;
import kodo.runtime.*;
public class Finder
     *     Usage: java reversetutorial.Finder <JDOQL query>
     public static void main (String[] args)
          if (args.length != 1)
               System.err.println ("Usage: java reversetutorial.Finder "
                    + "<JDOQL query>");
               return;
               executeCreatQuery();
     private static void executeCreatQuery ()
          Constructor[] constructors = NsConfig.class.getDeclaredConstructors
          for (int i = 0; i < constructors.length; i++)
                    // Find an appropriate constructor.
               Class[] paramTypes = constructors.getParameterTypes ();
               if (paramTypes.length == 2 &&
                         paramTypes[0] == String.class)
                    Object[] params = new Object[] {
                         "test", "50"
                    Object newObject = null;
                    try
                    newObject = constructors[i].newInstance (params);
                    } catch (Exception e) {
                         System.out.println("error!");
                    PersistenceManagerFactory pmf =
          KodoHelper.getPersistenceManagerFactory
("kodo.properties");
          PersistenceManager pm = pmf.getPersistenceManager ();
                    Transaction tx = pm.currentTransaction();
                    tx.begin();
                    pm.makePersistent(newObject);
                    tx.commit();
                    pm.close ();
                    pmf.close ();
2. NsConfig.java
package reversetutorial;
* Auto-generated by:
* kodo.jdbc.meta.ReverseMappingTool$ReverseCodeGenerator
public class NsConfig {
     private String key;
     private String value;
     public NsConfig() {
     public NsConfig(String key, String value) {
          this.key = key;
          this.value = value;
     public String getKey() {
          return key;
     public void setKey(String key) {
          this.key = key;
     public String getValue() {
          return value;
     public void setValue(String value) {
          this.value = value;

Answer 1

Odd. My guess is that maybe "key" is a reserved word in MySQL 4, but
was allowed during table creation for some reason. I assume this is a
fresh DB created by Kodo? If so, I would drop it, delete the .mapping
files for the classes, and start over after setting the following
configuration property:
kodo.jdbc.DBDictionary: ReservedWords=KEY