Release 340 (8 Aug 2020)

General

• Add support for query parameters in LIMIT, OFFSET and FETCH FIRST clauses. ({issue}4529, {issue}4601)
• Add experimental support for recursive queries. ({issue}4250)
• Add {func}bitwise_left_shift, {func}bitwise_right_shift and {func}bitwise_right_shift_arithmetic. ({issue}740)
• Add {func}luhn_check. ({issue}4011)
• Add IF EXISTS and IF NOT EXISTS syntax to ALTER TABLE. ({issue}4651)
• Include remote host in error info for page transport errors. ({issue}4511)
• Improve minimum latency for dynamic partition pruning. ({issue}4388)
• Reduce cluster load by cancelling query stages from which data is no longer required. ({issue}4290)
• Reduce query memory usage by improving retained size estimation for VARCHAR and CHAR types. ({issue}4123)
• Improve query performance for queries containing {func}starts_with. ({issue}4669)
• Improve performance of queries that use DECIMAL data type. ({issue}4730)
• Fix failure when GROUP BY clause contains duplicate expressions. ({issue}4609)
• Fix potential hang during query planning ({issue}4635).

Security

• Fix unprivileged access to table's schema via CREATE TABLE LIKE. ({issue}4472)

JDBC driver

• Fix handling of dates before 1582-10-15. ({issue}4563)
• Fix handling of timestamps before 1900-01-01. ({issue}4563)

Elasticsearch connector

• Fix failure when index mapping is missing. ({issue}4535)

Hive connector

• Allow creating a table with external_location when schema's location is not valid. ({issue}4069)
• Add read support for tables that were created as non-transactional and converted to be transactional later. ({issue}2293)
• Allow creation of transactional tables. Note that writing to transactional tables is not yet supported. ({issue}4516)
• Add hive.metastore.glue.max-error-retries configuration property for the number of retries performed when accessing the Glue metastore. ({issue}4611)
• Support using Java KeyStore files for Thrift metastore TLS configuration. ({issue}4432)
• Expose hit rate statistics for Hive metastore cache via JMX. ({issue}4458)
• Improve performance when querying a table with large files and with skip.header.line.count property set to 1. ({issue}4513)
• Improve performance of reading JSON tables. ({issue}4705)
• Fix query failure when S3 data location contains a _$folder$ marker object. ({issue}4552)
• Fix failure when referencing nested fields of a ROW type when table and partition metadata differs. ({issue}3967)

Kafka connector

• Add insert support for Raw data format. ({issue}4417)
• Add insert support for JSON. ({issue}4477)
• Remove unused kafka.connect-timeout configuration properties. ({issue}4664)

MongoDB connector

• Add mongodb.max-connection-idle-time properties to limit the maximum idle time of a pooled connection. ({issue}4483)

Phoenix connector

• Add table level property to specify data block encoding when creating tables. ({issue}4617)
• Fix query failure when listing schemas. ({issue}4560)

PostgreSQL connector

• Push down {func}count aggregations over constant expressions. For example, SELECT count(1). ({issue}4362)

SPI

• Expose information about query type in query Event Listener. ({issue}4592)
• Add support for TopN pushdown via the ConnectorMetadata.applyLimit() method. ({issue}4249)
• Deprecate the older variants of ConnectorSplitManager.getSplits(). ({issue}4508)