1. A system, comprising: a plurality of storage nodes, each of which comprises at least one processor and a memory, wherein the plurality of storage nodes is configured to collectively implement a distributed log-structured storage system of a database service configured to: receive a plurality of log records, from one or more database engine head nodes of the database service, wherein each of the plurality of log records is associated with a respective change to data stored by the database service and is further associated with a respective log sequence identifier; store the plurality of log records among the plurality of storage nodes; and transform the plurality of log records, wherein the plurality of log records include two or more log sections as operands for said transforming.