Release 1.4.0

Key Features

Area	Feature
Star Tree	1. Update APIs to support creating star tree cube for jdbc connectors 2. Implemented support for Clickhouse connector, support for additional JDBC based connectors will be added in the future 3. Bug fixes
Heuristic Index	1. Added support for UPDATE INDEX (see docs for details) 2. Added index size, memory usage and disk usage info in SHOW INDEX 3. Add mmap cache support for Bloom Index to reduce memory usage (enabled by default, see docs for details) 4. Dropping a table will now also drop any indexes associated with it 5. Index is now automatically load after creation (enabled by default, see docs for details)
Memory Connector	Fixed several important bugs to handle large data sets, and address incorrect results that occasionally occur for specific operators.
Task Recovery	Fixed several important bugs to address data inconsistency issues that occasionally occur during high concurrency, and during worker failures.
OLK-on-Yarn	Support deploying an openLooKeng cluster on yarn. The openLooKeng cluster can be deployed with a single coordinator, and multiple workers.
Low Latency	1. Optimized the Stats calculation for point queries which don’t contain join to speed up low latency queries 2. Added adaptive split grouping to enhance high concurrency query throughput 3. Support non-equality dynamic filters to speed up queries having predicates like <, >, <= & >=
Kylin Connector	Support read operations to the Kylin datasource

Category	Description	Gitee issue
Task Recovery	Concurrent CTAS, some SQL statements report the error “HiveSplitSource is already closed.”	144QYL
	An error occurs when the CTA creates a transaction table and inserts data"Unsuccessful query retry"	I44RQJ
OLK-on-Yarn	Multiple small openLooKeng clusters are started in the Hadoop cluster, but all openLooKeng cluster processes are on the same node. As a result, the openLooKeng cluster fails to be started	I4BP5A
	When multiple openLooKeng clusters are started, an error is reported when access some cluster CLI	I4BY6Z