A partitioning policy for materializing writes indicated in journal entries of a multi-data-store database is determined. The policy indicates a partitioning attribute of a data object. A write applier associated with a materialization node of the database processes journal entries according to the partitioning policy. If the value of the partitioning attribute associated with a write of a particular journal entry indicates that the write belongs to a partition materialized at the materialization node, the write applier propagates the write to the materialization node for storage at the node's storage devices.