The Teradata DBQL Tables Query logging includes a variety of table/view combinations in the DBC database: DBC.DBQLOGTBL and DBC.QryLogV Saves one row per query with the aggregated key figures like the number of CPU seconds, number of IOs, and much more. DBC.DBQLStepTbl and DBC.QryLogStepsVThe individual steps of a query are saved here, including the important

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What is a Teradata Query Band? The DBQL tables provide us with all the key figures we need to optimize queries. Because a Teradata system typically runs many thousands of queries per day, it is not easy to locate individual queries in the DQBL tables. It is, therefore, good practice to use the Teradata query

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How to Abort the Teradata Rollback Sometimes it happens that a DML statement on a large table causes a ROLLBACK to be executed, which runs for a very long time. Often you have to decide to wait until the ROLLBACK is finished or to abort the ROLLBACK. Canceling a rollback has the advantage that no

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Do you work in an environment where a Teradata compression tool is installed that conforms to your satisfaction? If not, I assume you are probably not very pleased with having to walk your way through the databases, table by table, to find out what to compress on which column. Typically, this is time-consuming, fatiguing, and

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Teradata Spool Space Introduction 4 Types of Teradata Spool Space IntermediateWill be released as soon as it is no longer needed. Intermediate Spool Space is required by derived subqueries, for example. The execution plan provides information about when spool space is released. OutputThe Output Spool Space holds the result of an SQL request. VolatileThey are

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A hot standby node is a member of a group of nodes (clique), and no virtual processes are running on it (AMPs, Parsing Engines). The hot standby node waits for its mission, which occurs when a node crashes out of its clique. Then all the AMPs of the crashed node are immediately migrated to the

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Types of Teradata Access Rights Teradata distinguishes between these four types of access rights: Implicit: The Teradata privileges of a user or database owning an object (“ownership privilege”) Explicit: The Privileges explicitly granted with the GRANT statement Inherited: The privileges inherited by being a role member Automatic: The privileges automatically granted by Teradata Owners and Creators Teradata distinguishes between creators and owners of database

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With the Teradata Version 16.00, some exciting features in Space Management have been introduced, which can bring enormous improvement in the daily activities in the administration and loading of the data warehouse. In my current environment, it regularly happens that the data warehouse’s daily loading is interrupted because there is not enough permanent space available

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This is just a short warning when you are upgrading to Teradata 16.20. We recently upgraded from Teradata 15.10 to 16.20 and detected that some of our reporting queries returned with each execution a different result set. Sometimes the result set was correct, sometimes wrong. After analyzing a little bit I found out that it’s

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