Teradata QueryGrid - Cloudera Distribution for Hadoop - 5.8, 5.9

Cloudera Distribution for Hadoop for Teradata Administrator Guide

prodname
Cloudera Distribution for Hadoop
vrm_release
5.8
5.9
category
Administration
featnum
B035-6049-086K

Teradata QueryGrid: Teradata Database-to-Hadoop

Teradata QueryGrid: Teradata-Hadoop connector provides a SQL interface for transferring data between Teradata Database and remote Hadoop hosts. It allows you to do the following:
  • Import Hadoop data into a temporary or permanent Teradata table
  • Export data from temporary or permanent Teradata tables into existing Hadoop tables
  • Create or drop tables in Hadoop from Teradata Database
  • Reference tables on the remote hosts in SELECT and INSERT statements
  • Select Hadoop data for use with a business tool
  • Select and join Hadoop data with data from independent data warehouses for analytical use
The Teradata QueryGrid: Teradata-Hadoop connector provides the following benefits:
  • The ability to export data to Hadoop servers
  • A simplified grammar, making the Teradata QueryGrid Teradata-to-Hadoop connector easier to use. After creating a foreign server once, you can then use the server name instead of providing detailed connection information for each SQL query.
  • The automatic push down of qualification columns and grammar to run on a remote host
  • The ability to qualify both columns and partitions involved in the query to reduce the amount of data returned
  • The ability to create an authorization object to securely store credentials. Foreign servers can be defined to use an authorization object to authenticate with a security system, such as LDAP or Kerberos, protecting Hadoop clusters.
    The Teradata QueryGrid Teradata-to-Hadoop connector does not currently support the use of Kerberos for external security.
  • Privileges to control who can read and write to the servers and tables on remote hosts

The syntax used for the connector is a Teradata extension to the ANSI SQL:2011 standard.

Teradata QueryGrid: Teradata Aster Database-to-Hadoop

Teradata QueryGrid Aster-Hadoop is a connector which provides access to Hadoop data tables using standard SQL queries in a low latency, data discovery environment. The table and storage management services for data stored in Hadoop is HCatalog. The connector provides deep metadata layer integration with Apache Hadoop HCatalog.

Some of the benefits of the connector are:
  • Querying HCatalog from Aster Database and supporting partitions and partition pruning on HCatalog to improve query performance
  • Using Aster Database to access the HCatalog metadata directly, and listing all databases and tables in HCatalog from Aster using the Aster Database cluster Terminal (ACT)
  • Using Aster Database to retrieve data from HCatalog, and automatically mapping HCatalog datatype value to the Aster datatype value
  • Enabling complex queries that include some data from Hadoop and some data from Aster Database through SQL
  • Extending the Aster Analytics library over data stored in Hadoop
  • Providing a simple way to load Hadoop data into Aster Database tables
  • Creating views of HCatalog data within Aster Database, which enables some business intelligence (BI) tools to generate queries against this HCatalog data

For information on connecting Aster Database to Hadoop nodes, including best-practices and network implementation strategies, and Teradata QueryGrid setup, refer to the Teradata Aster Big Analytics Appliance Database User Guide.