Ispirer SQLWays is a nice (although commercial) tool to convert DDL and data from one supported database to another. We are using it regularly, the list of supported databases is impressive: PostgreSQL, Greenplum, Oracle, SQL Server, IBM DB2, MySQL, Sybase, Informix, Teradata, *Netezza *and some more.
There’s just one thing which I always forget: SQLways exports all data by default, which makes the export unnecessary big and slow.