One or more table partitions may communicate with one or more index partitions. A communications channel may be dedicated to each combination of table partition and index partition. The communications channel may act as a queue of messages corresponding to updates to data maintained in a table partition that have yet to be processed by a corresponding index partition. Upon splitting a table partition, communications channels may be duplicated including unprocessed messages. Connections between new table partitions and an index may be finalized upon the index's receipt of a message indicative of the new table partition.