Release 0.90

Предупреждение

This release has a memory leak and should not be used.

General

• Initial support for partition and placement awareness in the query planner. This can result in better plans for queries involving JOIN and GROUP BY over the same key columns.

• Improve planning of UNION queries.

• Add presto version to query creation and completion events.

• Add property task.writer-count to configure the number of writers per task.

• Fix a bug when optimizing constant expressions involving binary types.

• Fix bug where a table writer commits partial results while cleaning up a failed query.

• Fix a bug when unnesting an array of doubles containing NaN or Infinity.

• Fix failure when accessing elements in an empty array.

• Fix «Remote page is too large» errors.

• Improve error message when attempting to cast a value to UNKNOWN.

• Update the approx_distinct() documentation with correct standard error bounds.

• Disable falling back to the interpreter when expressions fail to be compiled to bytecode. To enable this option, add compiler.interpreter-enabled=true to the coordinator and worker config properties. Enabling this option will allow certain queries to run slowly rather than failing.

• Improve JDBC драйвер conformance. In particular, all unimplemented methods now throw SQLException rather than UnsupportedOperationException.

Functions and language features

• Add bool_and() and bool_or() aggregation functions.

• Add standard SQL function every() as an alias for bool_and().

• Add year_of_week() function.

• Add regexp_extract_all() function.

• Add map_agg() aggregation function.

• Add support for casting JSON to ARRAY or MAP types.

• Add support for unparenthesized expressions in VALUES clause.

• Added SET SESSION, RESET SESSION and SHOW SESSION.

• Improve formatting of EXPLAIN (TYPE DISTRIBUTED) output and include additional information such as output layout, task placement policy and partitioning functions.

Hive

• Disable optimized metastore partition fetching for non-string partition keys. This fixes an issue were Presto might silently ignore data with non-canonical partition values. To enable this option, add hive.assume-canonical-partition-keys=true to the coordinator and worker config properties.

• Don’t retry operations against S3 that fail due to lack of permissions.

SPI

• Add getColumnTypes to RecordSink.

• Use Slice for table writer fragments.

• Add ConnectorPageSink which is a more efficient interface for column-oriented sources.

Примечание

This is a backwards incompatible change with the previous connector SPI. If you have written a connector, you will need to update your code before deploying this release.