Release 0.90

Warning

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

General Changes

  • 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 Driver 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 Changes

  • 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 Changes

  • Add getColumnTypes to RecordSink.
  • Use Slice for table writer fragments.
  • Add ConnectorPageSink which is a more efficient interface for column-oriented sources.

Note

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.