1. A method for transaction processing in a massively parallel processing (MPP) database, the method comprising: receiving, by a transaction manager, from a first resource manager, a first snapshot of the first resource manager; receiving, by the transaction manager, from a second resource manager, a second snapshot of the second resource manager; reconciling the first snapshot of the first resource manager and the second snapshot of the second resource manager to generate a reconciled snapshot; transmitting, by the transaction manager, to the first resource manager and the second resource manager, the reconciled snapshot; and performing a transaction using the reconciled snapshot.