PDI, Postgres and Transactions

Hi,

I've just started to work with Postgres

I have an Insert / Update step
for debugging I've set transaction size one record
I've defined error handling step

during the transformation one record is failed to insert due to unique constraint violation
this one record was handled and logged by error handling

next 4215 records was not processed with following error message
err_desc = org.pentaho.di.core.exception.KettleDatabaseException:
Error looking up row in database
ERROR: current transaction is aborted, commands ignored until end of transaction block

I'n new to Postgres, this exact setting used to work with MySQL
is it possible that I'm missing some parameters in connection setting ?