Presto 0.190 已发布，Presto 是 Facebook 开源的数据查询引擎，可对250PB以上的数据进行快速地交互式分析，查询的速度达到商业数据仓库的级别。据称该引擎的性能是 Hive 的 10 倍以上。 Presto 可以查询包括 Hive、Cassandra 甚至是一些商业的数据存储产品。单个 Presto 查询可合并来自多个数据源的数据进行统一分析。 General Changes Fix correctness issue for array_min() and array_max() when arrays contain NaN. Fix planning failure for queries involving GROUPING that require implicit coercions in expressions containing aggregate functions. Fix potential workload imbalance when using topology-aware scheduling. Fix performance regression for queries containing DISTINCT aggregates over the same column. Fix a memory leak that occurs on workers. Improve error handling when a HAVING clause contains window functions. Avoid unnecessary data redistribution when writing when the target table has the same partition property as the data being written. Ignore case when sorting the output of SHOW FUNCTIONS. Improve rendering of the BingTile type. The approx_distinct() function now supports a standard error in the range of [0.0040625, 0.26000]. Add support for ORDER BY in aggregation functions. Add dictionary processing for joins which can improve join performance up to 50%. This optimization can be disabled using the dictionary-processing-joins-enabled config property or the dictionary_processing_join session property. Add support for casting to INTERVAL types. Add ST_Buffer() geospatial function. Allow treating decimal literals as values of the DECIMAL type rather than DOUBLE. This behavior can be enabled by setting the parse-decimal-literals-as-double config property or the parse_decimal_literals_as_double session property to false. Add JMX counter to track the number of submitted queries. Resource Groups Changes Add priority column to the DB resource group selectors. Add exact match source selector to the DB resource group selectors. CLI Changes Add support for setting client tags. JDBC Driver Changes Add getPeakMemoryBytes() to QueryStats. Accumulo Changes Improve table scan parallelism. Hive Changes Fix query failures for the file-based metastore implementation when partition column values contain a colon. Improve performance for writing to bucketed tables when the data being written is already partitioned appropriately (e.g., the output is from a bucketed join). Add config property hive.max-outstanding-splits-size for the maximum amount of memory used to buffer splits for a single table scan. Additionally, the default value is substantially higher than the previous hard-coded limit, which can prevent certain queries from failing. Thrift Connector Changes Make Thrift retry configurable. Add JMX counters for Thrift requests. SPI Changes Remove the RecordSink interface, which was difficult to use correctly and had no advantages over the PageSink interface. 下载地址： Source code (zip) Source code (tar.gz) Presto 0.190 发布，Facebook 开源的大数据查询引擎下载地址
