PostgreSQL batch inserts fail silent randomly
With the help of the author of the script i used (sqlserver2pgsql) we realized it was a (new) issue with how Kettle handled parallel output table truncates.

https://github.com/dalibo/sqlserver2pgsql/issues/57#issuecomment-282675275

What happened was, and the reason i only lacked even hundreds of data, that the output job in some cases did run truncate after one or more workers already had done inserts on the table