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Offers practical, hands-on experience with retrieving & manipulating data with Teradata Structured Query Language (SQL) using both ANSI standard conventions & Teradata extensions.

Provides an overview of the Teradata Database architecture, as well as the features and benefits of the product. Teradata data distribution, access, storage and data protection methods are described. The suite of complementary load, access, and management utilities and tools are also covered, as well as Teradata Terminology.

Suppose you have a table with several non-unique secondary indexes (NUSI). When TPump loads the table, should you expect that each row’s INSERT will cause a table level lock on each of the secondary index sub-tables? And if so, couldn’t this create a lot of blocking across sessions?

Please  note:  This posting is relevant only to software releases prior to Teradata Database 14.0.  Ignore this recommendation if you are on 14.0 or greater software.

When you push too much paper into your shredder, it jams; when you pour too much coffee into your cup, it overflows; when you eat too much food, you…well, you know. Everything’s got limits.

I gave a presentation at the Teradata Partners Conference last week on the fundamentals of collecting statistics, where I touched briefly on the rules behind confidence levels. I’m using this article to go into further depth, and offer you more examples of how these confidence levels come about.

I was asked the other day about the request cache, speficially, how to keep plans in the cache so the query does not have to undergo repetitive parsing and optimizing.  A request cache exists on each parsing engine (PE) and will hold generic plans that have been identified as potentially re-usable.

Michael McIntire’s recent posting on NoPI tables (read it now!) got me thinking more and more about mini-batch, and how it’s growing in popularity.

The question of what Estimated Processing Time actually is comes up a lot. For example, the DBQLogTbl table carries an “EstProcTime” Value. If you are EXPLAIN-savy, then you’ve bumped up against “Estimated Time” numbers in almost every step of every query plan you’ve ever looked at.

Have you ever had what looks like a great query plan turn into life in the slow lane at run time?

This article provides a high-level overview of the process involved in moving to Teradata 13. Teradata 13 offers many new features and some of the highlights are covered in other articles on DEV/X. The focus here is how to get to Teradata 13.0.