AmbiguousTableNameException when multiple schemas have the tables with the same name

[jfrenetic]

Recently, I've bumped into another problem, while using APE Alpha5.

Our Oracle database has multiple schemas with the same set of tables.

When test method has annotation

@UsingDataSet("some_dataset.xml")

it fails with this exception:

org.jboss.arquillian.persistence.dbunit.exception.DBUnitDataSetHandlingException: Failed while seeding database.

          at org.jboss.arquillian.persistence.dbunit.DBUnitDataHandler.prepare(DBUnitDataHandler.java:81)

...

Caused by: org.dbunit.database.AmbiguousTableNameException: COUNTRIES

          at org.dbunit.dataset.OrderedTableNameMap.add(OrderedTableNameMap.java:198)

          at org.dbunit.database.DatabaseDataSet.initialize(DatabaseDataSet.java:231)

          at org.dbunit.database.DatabaseDataSet.getTableMetaData(DatabaseDataSet.java:281)

          at org.dbunit.operation.AbstractOperation.getOperationMetaData(AbstractOperation.java:80)

          at org.dbunit.operation.AbstractBatchOperation.execute(AbstractBatchOperation.java:140)

          at org.dbunit.operation.TransactionOperation.execute(TransactionOperation.java:78)

          at org.jboss.arquillian.persistence.dbunit.DBUnitDataHandler.fillDatabase(DBUnitDataHandler.java:144)

          at org.jboss.arquillian.persistence.dbunit.DBUnitDataHandler.prepare(DBUnitDataHandler.java:77)

When investigating a source code, I've found out a couple of things.

1) DBUnitConfiguration is built using the properties specified in arquillian.xml. So I can specify the "schema" property there (although, it's not documented anywhere). This could be  added to the DBUnit specific settings section of APE documentation

2) Another workaround would be to use qualifiedTableNames DBUnit feature.

3) But I don't like the above approaches, since they make my datasets non-portable. Since I run them using a DataSource configured on an application server, I'd like them to extract the schema information already configured there. So let's dive to the source code that initializes the org.dbunit.database.DatabaseConnection (particulary to the method org.jboss.arquillian.persistence.dbunit.DBUnitPersistenceTestLifecycleHandler.createDatabaseConnection()):

DataSource dataSource = dataSourceInstance.get();
final String schema = dbUnitConfigurationInstance.get().getSchema();
DatabaseConnection databaseConnection = null;
if (schema != null && schema.length() > 0)
{
     databaseConnection = new DatabaseConnection(dataSource.getConnection(), schema);
}
else
{
     databaseConnection = new DatabaseConnection(dataSource.getConnection());
}

Considering that the schema was not set during the initialization of DBUnitConfiguration, I'll get an exception later...

Could this be changed to something like this?

DataSource dataSource = dataSourceInstance.get();
final String schema = dbUnitConfigurationInstance.get().getSchema();
Connection jdbcConnection = dataSource.getConnection();
String userName = jdbcConnection.getMetaData().getUserName();
DatabaseConnection databaseConnection = null;
if (schema != null && schema.length() > 0)
{
         databaseConnection = new DatabaseConnection(jdbcConnection, schema);
} else if (userName != null)
{
          databaseConnection = new DatabaseConnection(jdbcConnection, userName);
} else
{
         databaseConnection = new DatabaseConnection(jdbcConnection);
}

Or will it be Database Vendor-dependent? (since it might be, that not every database has one-to-one relation between userName and schema)

Aside from that, I've noticed a possible connection leak again

Take a look at this:

try
{
  //...
  if (schema != null && schema.length() > 0)
  {
       databaseConnection = new DatabaseConnection(dataSource.getConnection(), schema);
  }
  //...
 databaseConnection.getConfig().setProperty(DatabaseConfig.PROPERTY_DATATYPE_FACTORY,
               new DefaultDataTypeFactory());
         databaseConnectionProducer.set(databaseConnection);

} 
catch (Exception e)
{
      throw new DBUnitInitializationException("Unable to initialize database connection for dbunit module.", e);
}

If an exception happen during the construction of DatabaseConnection or at some other point later, the jdbcConnection won't be released properly.

[bmajsak]

You are true hero with these detailed descriptions it simply makes my life way easier! Kudos!

I was just wondering - since you digging into the code anyway how about making a pull requests for some weird things you noticed?

Cheers,

Bartosz

[jfrenetic]

Thanks, Bartosz! I actually quite enjoy digging the source code of Arquillian, since there is a lot of useful stuff to learn I must admit though, that I'd never worked with Git before (I've been using SVN for years). So, I'm willing to help, but have to take a quick tour of Git when I have spare time. Also, do I need special permissions to make a pull request?

[bmajsak]

With regards to git it's very easy to get started - this might be a good starting point http://learn.github.com/p/intro.html

I've been using SVN for years too and switching to git from my experience is quite straightforward (even though conceptually it's way different). There just a bit of things to understand (like different meaning of commit), but it's quick stuff for most of the essential operations.

For pull requests you simply fork repository and you work on your local copy and once you are done you simply make pull request to upstream repo (from which you fork).

This might be helpful to some extent https://community.jboss.org/wiki/ShrinkWrapDevelopmentAndContribution

In any case just shout here, I'm more than happy to help.

[jfrenetic]

Thanks for the links! Although the first one is broken, it's available from Google cache

I'll definitely consider an opportunity to make a pull request, next time I find something weird Open Source is awesome