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Teradata Alerts / CAM 14.0 released

Teradata is pleased to announce the Teradata Alerts / Common Alerting Mechanism (CAM) 14.0 release effective March 14th, 2012. A few of the key feature additions include running actions on Linux, a new "run SQL" action, incremental backups, and usability updates to the Alert Viewer portlet.

Introducing Aster Express

We are very excited to introduce the Aster Express for VMware Player images.  Much like the very popular Teradata Express program, these downloadable Aster virtual images will provide customers with a free evaluation version of the Aster analytic platform that can be run on their PC.  While this Express edition is not licensed for production usage, it is a fully functional Aster cluster that is a great tool for developers and testers or anyone else who wants a hands-on introduction to this Big Data analytics platform.  Over the coming weeks and months here on Teradata's Developer Exchange, we will be publishing Aster tutorials, along with sample datasets, that will highlight the powers of this exciting platform.

Aster Express - Getting Started

Aster Express virtual images are now available for downloading to your PC so that you can run an Aster cluster.  After installing VMware Player and downloading the Aster Queen and Worker images (see the Introduction to Aster Express article), you're ready to bring the Aster cluster to life! 

Where do the rows go?

With row partitioning (for a PPI or column-partitioned table), the Teradata Database makes sure rows are placed in their appropriate partitions.  When the row partitioning for the table is altered, rows may need to move from one partition to another so they are in their appropriate partitions according to the altered partitioning.  The partitioning expression must be deterministic (always computes the same value for the same value of the partitioning column) to properly place and retrieve the row.

For instance if the table has RANGE_N partitioning, ALTER TABLE will move rows automatically from NO RANGE to newly-added ranges as needed.  Also, if a range is dropped, rows from that partition are moved to the NO RANGE, NO RANGE OR UNKNOWN partition or a newly-added range that covers the dropped range.

JDBC ResultSet Pagination

"Pagination" refers to the technique commonly used by web applications to display a section of a larger query result, and let the user jump backwards and forwards to particular sections. Google, for example, uses this technique to display search results.

This article assumes that your queries routinely return more row data than can fit into a single 1 MB response message sent from the Teradata Database to the Teradata JDBC Driver.

Let's talk about Surrogate Key Generation

There are data models that use surrogate keys as part of primary key/primary index definition.

Examples are: Industry and Homegrown models.

The use of surrogate keys is usually considered when loading different source systems with different natural keys on the same integrated data model. This implies a conversion of the different natural keys into a standard surrogate key that can be used for all source systems.

Bottom of the Pyramid

Schumpeter’s blog had (yet another) interesting entry a couple of weeks back:  “Now for some good news.”  It reviews a couple of authors’ view that we are on the cusp of future abundance due to upcoming technical breakthroughs.  The four drivers of the future are listed as the:

How to determine or switch the current database using the Teradata JDBC Driver

Question

We can establish a JDBC Connection with URL that specifies a database name, e.g.

jdbc:teradata://<some host>/DATABASE=<some database>

After the Connection is opened, is there any way to determine what database is in use? And is there any way to switch to a different database?

Answer

What's new in Teradata SQL Assistant 14.01

  

This article will introduce the new features and UI enhancements that have been added to Teradata SQL Assistant 14.01. The focus of this release is on usability and the introduction of Charting and the direct editing of Table data.

This article assumes that you are already familiar with the features in SQL Assistant 13.11. If not, you may wish to read the following articles first:

Derived Tables with Ordered Analytical Functions to Translate Flat Logic

Ordered analytical functions enable parallel processing by freeing processes from flat logic. They also produce simpler Set SQL statements, which as a general rule can be expected to perform better than more complex Set SQL statements.

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