difference between datasource and transcation datasource in ejb

[Ramamoorthy]

Hi,
can you tell the difference between data source and transcation data source and in what conditions we should use them?
Ram

[Seetesh Hindlekar]

Hi,
Using Weblogic 7.0,
When U define a CMP Entity Bean, u use TX Datasource and
when u define a BMP Entity Bean, u use the DataSource in the code defined in any method accessing the Database using the following syntax.
private Connection getConnection() throws SQLException
{ InitialContext initCtx = null;
try
{
initCtx = new InitialContext();
DataSource ds = (javax.sql.DataSource)initCtx.lookup("orasource");
return ds.getConnection();
}
............
}
HTH,
Seetesh

[Matt Warsaw]

Always Use A Transactional Datasource for Container-Managed EJBs
If you configure a JDBC datasource factory for use with container-managed EJBs, make sure you configure a transactional datasource (TXDataSource) rather than a non-transactional datasource (DataSource).
With a non-transactional datasource, the JDBC connection operates in auto commit mode, committing each insert and update operation to the database immediately, rather than as part of a container-managed transaction.

[Roland Barcia]

Most data sources are transactional. In essence, a database operation that does an updaqte executes in autom-commit mode which is a transaction with a single operation.
So when you do a query (without a for update), it is not a transaction?
Perhaps you mean what is the difference between an XA and NONXA data source?

[Vishwa Kumba]

When do we use non-transactional datasources?