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I have a quick question regarding processing of views.

I have a query where teradata expain is giving wrong esitmated time though the query is taking very few seconds.
It is estimating 9 mins due to which it is getting throttled.  Issue is in step 7. All the stats are ok and refreshed.
Could anyone pleae suggest what might be wrong.



Whether you write your own code or it is generated for you, this is a topic that is essential for business users who run SQL queries.

Greetings experts,

This presentation builds on Recorded Webcast # 49911 Explaining the EXPLAIN, which did just that (if you have not viewed, please do so before watching this webcast).

I've just started playing around with column partitioning in R14. I created a table using a recent example that Paul Sinclair put into a recent Teradata Magazine article:

This presentation follows a Teradata SQL query from its origin at the client through the components of the parsing engine (PE), dispatched execution steps through the BYNET, step execution and file system management in the access module processor (AMP), merge and sorting of the response through the BYNET to the PE, and returning the answer set to the client.

A topic that is essential for all SQL programmers and database designers. This session examines the mysteries of the English text that appears when an EXPLAIN is requested.

Is there a permission that will allow a particular user (ME) to execute an EXPLAIN of Sql that updates or inserts into tables or selects from tables  that  I don't have update or insert or select permissions on?  (or creates a table in a database that the "Explaining user" doesn't have permission to)?

Have you ever been bewildered trying to tune complex Teradata queries that go on for pages and pages of EXPLAIN text?  This presentation goes beyond "Explain the Explain", to teach strategies and techniques for quickly deciphering the most expensive operations in your queries.  Taught by a 20+ year Teradata veteran, examples of real queries gathered from some of the largest production environments in the world are used.  This is advanced material covered at a quick pace.

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.

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.