Release 0.170

    • Fix a performance regression for GROUP BY queries over UNION.

    • Fix a performance regression that occurs when a significant number of exchange sources produce no data during an exchange (e.g., in a skewed hash join).

    Web UI Changes

    • Fix broken rendering when catalog properties are set.

    • Add support for .

    Hive Changes

    • Improve decimal support for the Parquet reader.

    • Fix an intermittent connection issue for Cassandra 2.1.

    • Remove partition key cache to improve consistency and reduce load on the Cassandra cluster due to background cache refresh.

    • Reduce the number of connections opened to the Cassandra cluster. Now Presto opens a single connection from each node.

    • Use exponential backoff for retries when Cassandra hosts are down. The retry timeout can be controlled via the config option, which has a default value of 1m. The cassandra.no-host-available-retry-count config option is no longer supported.

    Verifier Changes

    • Add support for queries.