Cloudera Impala Review Sheet

There has been a lot of constant interest in Cloudera Impala, which enables real-time, interactive analytical queries of the data stored in HBase or HDFS.
Below is a review sheet for Cloudera Impala based on multiple sources. Feel free to document anything which you may know differently.

What’s there:

-          USP:
o       Low latency querying for HDFS
-          Business Use case:
o       Can be used for near real time operations
-          Key Components:
o       Daemon : impalad – low latency daemon running on each datanode (mutually exclusive of MapReduce)
o       StateStore: Impala StateStore – high throughput scheduler which stores state of daemon running on nodes, also provides subscription service, thrift mode, failure detection (also for HA)
o       Shell: Impala Shell - standard querying interface
-          Production Ready Version



What’s not there (in current release):

-          Resource Manager
-          User Defined Function support for Hive
-          Delay Scheduling
-          Manual query aborts
-          DDL Statements
-          Procedures, Scheduled jobs


What to expect (in current release):

-          SQL-92 features of Hive Query language
-          Low latency start and fetch
-          ODBC support, Command Line Interface for querying
-          Kerberos authentication
-          Possible lesser cost of ownership than licensed counterparts like Hadapt

What not to expect (in current release):

-          RDBMS speed in all operations
-          Trevni support which will bring in support for columnar binary storage and   more compression options
-          Lot of consistent documentation

When to expect new features:

-          Q1’2013 for a more stable version
-          More feature loaded version in CDH5

Which are the closest product match:

-          Google F1
-          RAD labs Sparrow BatchSampling

How to update yourself

-          Impala mailing list
-          Cloudera blog


Where to download:

-          Beta Release

-          Documentation
-          Code
selective snapshot below: 



update: 6 Dec 2012: Title of post changed based on review comments received to sound more technically correct.