Updating Schemas in Custom Snapshots

I am working on a custom snapshot based on the Data Ware house extension articlehttp://www.ibm.com/developerworks/rational/library/add-a-rational-team-concert-data-warehouse-extension-for-custom-attributes/index.html?ca=drs-.

I am using an RTC 2.0.0.2 instance with Apache Derby as the database implementation.

When I try to modify the schema of a table or view I get the following error:

2011-12-08 10:59:11,423 The user "ADMIN" has logged in to the database "repositoryDB".
2011-12-08 10:59:11,429 Adding tables to the database "repositoryDB".
2011-12-08 10:59:12,183 CRJAZ1374E The table named "LINK_HISTORY" failed to be added to the schema named "CUSTOM_HISTORY_SNAPSHOT".
com.ibm.team.repository.common.TeamRepositoryException: CRJAZ0827I Failed to save the table name in table map.
at com.ibm.team.repository.service.internal.schemagen.PersistentMappingService.saveTableOrViewName(PersistentMappingService.java:414)
at com.ibm.team.repository.service.internal.schemagen.PersistentMappingService.saveTableName(PersistentMappingService.java:396)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.invoke(ExportProxyServiceRecord.java:370)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.access$0(ExportProxyServiceRecord.java:356)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord$ExportedServiceInvocationHandler.invoke(ExportProxyServiceRecord.java:56)
at $Proxy35.saveTableName(Unknown Source)
at com.ibm.team.repository.service.internal.rdb.AbstractDatabaseService.internalCreateAndSaveTable(AbstractDatabaseService.java:348)
at com.ibm.team.repository.service.internal.rdb.AbstractDatabaseService.internalUpdateContributedSchemas(AbstractDatabaseService.java:299)
at com.ibm.team.repository.service.internal.rdb.AbstractDatabaseService.internalUpdateAllSchemas(AbstractDatabaseService.java:222)
at com.ibm.team.repository.service.internal.rdb.DatabaseMaintenanceService$8.run(DatabaseMaintenanceService.java:182)
at com.ibm.team.repository.service.internal.rdb.ConnectionRunnable.run(ConnectionRunnable.java:34)
at com.ibm.team.repository.service.internal.rdb.RepositoryDatabase$Transaction.run(RepositoryDatabase.java:466)
at com.ibm.team.repository.service.internal.rdb.RepositoryDatabase$1.run(RepositoryDatabase.java:292)
at com.ibm.team.repository.service.internal.rdb.ConnectionPoolService.withCurrentConnection(ConnectionPoolService.java:331)
at sun.reflect.GeneratedMethodAccessor23.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.invoke(ExportProxyServiceRecord.java:370)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.access$0(ExportProxyServiceRecord.java:356)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord$ExportedServiceInvocationHandler.invoke(ExportProxyServiceRecord.java:56)
at $Proxy22.withCurrentConnection(Unknown Source)
at com.ibm.team.repository.service.internal.rdb.RepositoryDatabase.runTransaction(RepositoryDatabase.java:288)
at com.ibm.team.repository.service.internal.rdb.RepositoryDatabase.runExclusive(RepositoryDatabase.java:267)
at com.ibm.team.repository.service.internal.TransactionService.runExclusive(TransactionService.java:89)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.invoke(ExportProxyServiceRecord.java:370)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.access$0(ExportProxyServiceRecord.java:356)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord$ExportedServiceInvocationHandler.invoke(ExportProxyServiceRecord.java:56)
at $Proxy44.runExclusive(Unknown Source)
at com.ibm.team.repository.service.internal.rdb.DatabaseMaintenanceService.updateAllSchemas(DatabaseMaintenanceService.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.invoke(ExportProxyServiceRecord.java:370)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord.access$0(ExportProxyServiceRecord.java:356)
at org.eclipse.soda.sat.core.internal.record.ExportProxyServiceRecord$ExportedServiceInvocationHandler.invoke(ExportProxyServiceRecord.java:56)
at $Proxy61.updateAllSchemas(Unknown Source)
at com.ibm.team.repotools.commands.local.internal.AddTablesCommand.addTables(AddTablesCommand.java:39)
at com.ibm.team.repotools.commands.local.internal.AddTablesCommand.execute(AddTablesCommand.java:73)
at com.ibm.team.repotools.command.AbstractCommand.execute(AbstractCommand.java:48)
at com.ibm.team.repotools.rcp.internal.RepositoryToolsApplication.run(RepositoryToolsApplication.java:727)
at com.ibm.team.repotools.rcp.internal.RepositoryToolsApplication.start(RepositoryToolsApplication.java:764)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:386)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:618)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
at org.eclipse.equinox.launcher.Main.run(Main.java:1236)
at org.eclipse.equinox.launcher.Main.main(Main.java:1212)
Caused by:
java.sql.SQLException: The statement was aborted because it would have caused a duplicate key value in a unique or primary key constraint or unique index identified by 'TABLE_MAP_PK' defined on 'TABLE_MAP'.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.generateCsSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.TransactionResourceImpl.wrapInSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.TransactionResourceImpl.handleException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.handleException(Unknown Source)
at org.apache.derby.impl.jdbc.ConnectionChild.handleException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedStatement.executeStatement(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedPreparedStatement.executeStatement(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedPreparedStatement.execute(Unknown Source)
at com.ibm.team.repository.service.internal.db.jdbcwrappers.stat.PreparedStatementStatWrapper.execute(PreparedStatementStatWrapper.java:51)
at com.ibm.team.repository.service.internal.db.jdbcwrappers.errlog.PreparedStatementErrLogWrapper.execute(PreparedStatementErrLogWrapper.java:65)
at com.ibm.team.repository.service.internal.db.jdbcwrappers.leak.PreparedStatementLeakWrapper.execute(PreparedStatementLeakWrapper.java:50)
at com.ibm.team.repository.service.internal.schemagen.PersistentMappingService.saveTableOrViewName(PersistentMappingService.java:408)
... 62 more

These errors occur even when I have used a SQL client (SQuirreL) to drop the tables, views, and snapshot schemas.

Renaming the table, view, and snapshots are not acceptable workarounds in a production environment should I need to modify the schema in the future. Is there a step that I am missing?