20.50. Release 0.190
- Fix correctness issue for
array_max()when arrays contain
- Fix planning failure for queries involving
GROUPINGthat require implicit coercions in expressions containing aggregate functions.
- Fix potential workload imbalance when using topology-aware scheduling.
- Fix performance regression for queries containing
DISTINCTaggregates over the same column.
- Fix a memory leak that occurs on workers.
- Improve error handling when a
HAVINGclause 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
- Improve rendering of the
approx_distinct()function now supports a standard error in the range of
- Add support for
ORDER BYin 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-enabledconfig property or the
- Add support for casting to
- Allow treating decimal literals as values of the
DECIMALtype rather than
DOUBLE. This behavior can be enabled by setting the
parse-decimal-literals-as-doubleconfig property or the
parse_decimal_literals_as_doublesession property to
- 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.
- Add support for setting client tags.
JDBC Driver Changes
- Improve table scan parallelism.
- 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-sizefor 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.
- Remove the
RecordSinkinterface, which was difficult to use correctly and had no advantages over the
This is a backwards incompatible change with the previous connector SPI.
If you have written a connector that uses the
you will need to update your code before deploying this release.