Cloudera Engineering Blog · Impala Posts
The following post, by Sarah Cannon of Digital Reasoning, was originally published in that company’s blog. Digital Reasoning has graciously permitted us to re-publish here for your convenience.
At the beginning of each release cycle, engineers at Digital Reasoning are given time to explore the latest in Big Data technologies, examining how the frequently changing landscape might be best adapted to serve our mission. As we sat down in the early stages of planning for Synthesys 3.8 one of the biggest issues we faced involved reconciling the tradeoff between flexibility and performance. How can users quickly and easily retrieve knowledge from Synthesys without being tied to one strict data model?
The CDH software stack lets you use your tool of choice with the Parquet file format – - offering the benefits of columnar storage at each phase of data processing.
An open source project co-founded by Twitter and Cloudera, Parquet was designed from the ground up as a state-of-the-art, general-purpose, columnar file format for the Apache Hadoop ecosystem. In particular, Parquet has several features that make it highly suited to use with Cloudera Impala for data warehouse-style operations:
This quick demo illustrates how easy it is to implement role-based access and control in Impala using Sentry.
Apache Sentry (incubating) is the Apache Hadoop ecosystem tool for role-based access control (RBAC). In this how-to, I will demonstrate how to implement Sentry for RBAC in Impala. I feel this introduction is best motivated by a use case.
Cloudera’s own enterprise data hub is yielding great results for providing world-class customer support.
Here at Cloudera, we are constantly pushing the envelope to give our customers world-class support. One of the cornerstones of this effort is the Cloudera Support Interface (CSI), which we’ve described in prior blog posts (here and here). Through CSI, our support team is able to quickly reason about a customer’s environment, search for information related to a case currently being worked, and much more.
Hadoop 2.3.0 includes hundreds of new fixes and features, but none more important than HDFS caching.
The Apache Hadoop community has voted to release Hadoop 2.3.0, which includes (among many other things):
Bringing Parquet support to Hive was a community effort that deserves congratulations!
Previously, this blog introduced Parquet, an efficient ecosystem-wide columnar storage format for Apache Hadoop. As discussed in that blog post, Parquet encodes data extremely efficiently and as described in Google’s original Dremel paper. (For more technical details on the Parquet format read Dremel made simple with Parquet, or go directly to the open and community-driven Parquet Format specification.)
Thanks to Xavier Clements of Wajam for allowing us to re-publish his blog post about Wajam’s Hadoop experiences below!
Wajam is a social search engine that gives you access to the knowledge of your friends. We gather your friends’ recommendations from Facebook, Twitter, and other social platforms and serve these back to you on supported sites like Google, eBay, TripAdvisor, and Wikipedia.
Cloudera provides docs and a sample build environment to help you get easily started writing your own Impala UDFs.
User-defined functions (UDFs) let you code your own application logic for processing column values during a Cloudera Impala query. For example, a UDF could perform calculations using an external math library, combine several column values into one, do geospatial calculations, or other kinds of tests and transformations that are outside the scope of the built-in SQL operators and functions.
Impala’s speed now beats the fastest SQL-on-Hadoop alternatives. Test for yourself!
Since the initial beta release of Cloudera Impala more than one year ago (October 2012), we’ve been committed to regularly updating you about its evolution into the standard for running interactive SQL queries across data in Apache Hadoop and Hadoop-based enterprise data hubs. To briefly recap where we are today:
With the close of 2013, we also thought it appropriate to include some high points from across the year (not listed in any particular order):