Page History

...

If you create a Pre-Aggregate Table ('preaggregate' DataMap) on a partitioned main table, the Pre-Aggregate Table is also partitioned based on the same column. Since the partition is aligned, when you perform data management operation like create/drop/overwrite on the main table, the same operation will be done automatically on the aggregate table, keeping both in sync.

Materialized View (Alpha feature)

Materialized View is integrated as a DataMap in CarbonData, it provides pre-aggregation for SPJGH-like table (select-prodicate-join-groupby-having).  User can use existing DataMap statement to create, drop, show Materialized Views. While querying, system finds good MVs based on cost for query rewrite to improve query performance.

DataMap Management Enhancement

A new syntax 'DEFERRED REBUILD' is introduced in CREATE DATAMAP statement, this enables user choose DataMap management mechanism (automatic or manual) when creating the DataMap. When 'DEFERRED REBUILD' is specified, DataMap is by default disabled, and data loading to main table will not trigger loading to DataMap until user performs REBUILD DATAMAP.

Enhanced Data Load performance

...